replace canvas-based HybridBinarizer round-trip with in-memory GlobalHistogramBinarizer path — no DOM needed, works in both browser and node, eliminates AZTEC_CONTENT_MISMATCH root cause; add 200-payload unit test, 20-envelope integration test, and 100KB vault pipeline test (204 tests passing)

@@ -1,29 +1,38 @@11 /**22  * aztec.ts — Aztec 2D barcode generation with round-trip verification.33  *4- * Browser path: ZXing's AztecEncoder renders to OffscreenCanvas → PNG.5- *   Using the same library for both encoding and decoding guarantees6- *   round-trip compatibility. bwip-js's mode-encoding choices (LATCH/SHIFT7- *   sequences) differed from ZXing's decoder expectations on certain data8- *   patterns, causing systematic AZTEC_CONTENT_MISMATCH errors. Switching9- *   to ZXing's own AztecEncoder eliminates the incompatibility entirely and10- *   also removes the 918 kB bwip-js chunk from all browser builds.4+ * Encode path (both environments): ZXing AztecEncoder → BitMatrix.115  *12- * Node/test path: bwip-js/node → PNG Buffer.13- *   OffscreenCanvas is unavailable in vitest; round-trip verification is14- *   skipped (decodeAztecFromPng returns null without a DOM). The generation15- *   tests for that path cover the encoder via separate code paths.6+ * Verification: in-memory BitMatrix → Int32Array → GlobalHistogramBinarizer →7+ *   AztecCodeReader. No canvas, no PNG decode, no DOM. Works identically in8+ *   the browser popup and in vitest's node environment.9+ *10+ *   GlobalHistogramBinarizer is used rather than HybridBinarizer because the11+ *   latter is tuned for camera images with spatially uneven illumination. On12+ *   synthetically-generated images (perfectly flat black/white pixels) the13+ *   local-block threshold inside HybridBinarizer can misclassify an all-black14+ *   region (e.g. the Aztec bull's-eye) as white, producing a spurious decode.15+ *   A global histogram threshold has no such blind spot.16+ *17+ * PNG render path:18+ *   Browser — ZXing BitMatrix → OffscreenCanvas → PNG.19+ *   Node/test — bwip-js/node (OffscreenCanvas unavailable in vitest). The20+ *     bwip-js PNG is used only for the PDF pipeline test; all correctness21+ *     verification already happened via the in-memory path.1622  */1723 1824 import {25+  AztecCodeReader,1926   AztecEncoder,20-  BarcodeFormat,2127   BinaryBitmap,28+  BarcodeFormat,2229   DecodeHintType,30+  GlobalHistogramBinarizer,2331   HybridBinarizer,2432   MultiFormatReader,2533   RGBLuminanceSource,2634 } from "@zxing/library";35+import type { BitMatrix } from "@zxing/library";2736 import {2837   AZTEC_ECC_PERCENT,2938   CodexError,@@ -36,55 +45,97 @@3645   height: number;3746 }3847 39-// ── Browser: ZXing Aztec encoding ────────────────────────────────────────────48+// ── Matrix building ───────────────────────────────────────────────────────────4049 4150 /**42- * Render an Aztec barcode using ZXing's own encoder at 25% ECC, scale 4,43- * with a 2-module quiet zone. Using ZXing to both encode and decode guarantees44- * round-trip fidelity; the encoder uses the same HighLevelEncoder mode tables45- * that the decoder expects, so no mode-switching incompatibility is possible.51+ * Encode `payload` (ISO-8859-1 bytes = ASCII for our JSON envelopes) into a52+ * ZXing Aztec BitMatrix at 25% ECC with automatic layer selection.4653  */47-async function generateAztecPngBrowser(payload: string): Promise<AztecImage> {48-  // Encode payload as ISO-8859-1 bytes (= ASCII for our JSON envelope).54+export function buildAztecMatrix(payload: string): BitMatrix {4955   const dataBytes = new Uint8Array(payload.length);5056   for (let i = 0; i < payload.length; i++) dataBytes[i] = payload.charCodeAt(i);57+  const aztecCode = AztecEncoder.encode(dataBytes, AZTEC_ECC_PERCENT, 0 /* auto layers */);58+  const matrix = aztecCode.getMatrix();59+  if (!matrix) throw new Error("AztecEncoder returned null matrix");60+  return matrix;61+}5162 52-  try {53-    const aztecCode = AztecEncoder.encode(dataBytes, AZTEC_ECC_PERCENT, 0 /* auto layers */);54-    const matrix = aztecCode.getMatrix();55-    if (!matrix) throw new Error("encoder returned null matrix");63+// ── In-memory round-trip verification ─────────────────────────────────────────5664 57-    const modules = matrix.getWidth(); // Aztec codes are always square58-    const scale = 4;59-    const pad = 2 * scale; // 2-module quiet zone (8 px at scale 4)60-    const size = modules * scale + pad * 2;65+/**66+ * Decode `matrix` in memory and confirm it reads back as `payload`.67+ *68+ * Builds a pixel array directly from the BitMatrix — no canvas, no PNG, no69+ * OffscreenCanvas — so this works in both the browser popup and in vitest's70+ * node environment. Uses GlobalHistogramBinarizer (global threshold) which is71+ * appropriate for synthetically-perfect images.72+ */73+export function verifyMatrixRoundTrip(matrix: BitMatrix, payload: string): boolean {74+  const modules = matrix.getWidth(); // Aztec codes are always square75+  const scale = 4;76+  const pad = 2 * scale; // 2-module quiet zone = 8px at scale 477+  const imgW = modules * scale + pad * 2;78+  const imgH = imgW;6179 62-    const canvas = new OffscreenCanvas(size, size);63-    const ctx = canvas.getContext("2d")!;64-    ctx.fillStyle = "#ffffff";65-    ctx.fillRect(0, 0, size, size);66-    ctx.fillStyle = "#000000";67-    for (let y = 0; y < modules; y++) {68-      for (let x = 0; x < modules; x++) {69-        if (matrix.get(x, y)) {70-          ctx.fillRect(pad + x * scale, pad + y * scale, scale, scale);80+  // RGBLuminanceSource wants packed 32-bit ARGB as a signed Int32Array.81+  const WHITE = -1; // 0xFFFFFFFF as signed int3282+  const BLACK = (0xff << 24) | 0; // 0xFF000000 as signed int32 = -1677721683+84+  const argb = new Int32Array(imgW * imgH);85+  argb.fill(WHITE);86+87+  for (let y = 0; y < modules; y++) {88+    for (let x = 0; x < modules; x++) {89+      if (matrix.get(x, y)) {90+        const baseRow = (pad + y * scale) * imgW + pad + x * scale;91+        for (let dy = 0; dy < scale; dy++) {92+          for (let dx = 0; dx < scale; dx++) {93+            argb[baseRow + dy * imgW + dx] = BLACK;94+          }7195         }7296       }7397     }98+  }7499 75-    const blob = await canvas.convertToBlob({ type: "image/png" });76-    const pngBytes = new Uint8Array(await blob.arrayBuffer());77-    return { pngBytes, width: size, height: size };78-  } catch (err) {79-    throw new CodexError(80-      "AZTEC_GENERATION_FAILED",81-      `Aztec render failed: ${err instanceof Error ? err.message : String(err)}`,82-    );100+  try {101+    const source = new RGBLuminanceSource(argb, imgW, imgH);102+    const binarizer = new GlobalHistogramBinarizer(source);103+    const bitmap = new BinaryBitmap(binarizer);104+    const reader = new AztecCodeReader();105+    return reader.decode(bitmap).getText() === payload;106+  } catch {107+    return false;83108   }84109 }85110 86-// ── Node/test: bwip-js path ───────────────────────────────────────────────────111+// ── PNG rendering — browser path ──────────────────────────────────────────────87112 113+async function matrixToPngBrowser(matrix: BitMatrix): Promise<AztecImage> {114+  const modules = matrix.getWidth();115+  const scale = 4;116+  const pad = 2 * scale;117+  const size = modules * scale + pad * 2;118+119+  const canvas = new OffscreenCanvas(size, size);120+  const ctx = canvas.getContext("2d")!;121+  ctx.fillStyle = "#ffffff";122+  ctx.fillRect(0, 0, size, size);123+  ctx.fillStyle = "#000000";124+  for (let y = 0; y < modules; y++) {125+    for (let x = 0; x < modules; x++) {126+      if (matrix.get(x, y)) {127+        ctx.fillRect(pad + x * scale, pad + y * scale, scale, scale);128+      }129+    }130+  }131+132+  const blob = await canvas.convertToBlob({ type: "image/png" });133+  const pngBytes = new Uint8Array(await blob.arrayBuffer());134+  return { pngBytes, width: size, height: size };135+}136+137+// ── PNG rendering — node/test path ────────────────────────────────────────────138+88139 interface BwipNodeModule {89140   toBuffer: (opts: Record<string, unknown>) => Promise<Buffer>;90141 }@@ -101,7 +152,7 @@101152   return merged;102153 }103154 104-async function generateAztecPngNode(payload: string): Promise<AztecImage> {155+async function matrixToPngNode(payload: string): Promise<AztecImage> {105156   const mod = await loadBwipNode();106157   const opts = {107158     bcid: "azteccode",@@ -112,17 +163,10 @@112163     monochrome: true,113164   } as const;114165 115-  try {116-    const buf = await mod.toBuffer(opts);117-    const pngBytes = new Uint8Array(buf.buffer, buf.byteOffset, buf.byteLength).slice();118-    const { width, height } = readPngDimensions(pngBytes);119-    return { pngBytes, width, height };120-  } catch (err) {121-    throw new CodexError(122-      "AZTEC_GENERATION_FAILED",123-      `Aztec render failed: ${err instanceof Error ? err.message : String(err)}`,124-    );125-  }166+  const buf = await mod.toBuffer(opts);167+  const pngBytes = new Uint8Array(buf.buffer, buf.byteOffset, buf.byteLength).slice();168+  const { width, height } = readPngDimensions(pngBytes);169+  return { pngBytes, width, height };126170 }127171 128172 /** Read a PNG's IHDR width/height. PNGs always have IHDR as the first chunk. */@@ -137,40 +181,37 @@137181   return { width, height };138182 }139183 140-// ── Aztec PNG generation (public) ────────────────────────────────────────────184+// ── Public: Aztec PNG generation ──────────────────────────────────────────────141185 142186 /**143187  * Render an Aztec barcode and return its PNG bytes + dimensions.144- * Browser: ZXing AztecEncoder → OffscreenCanvas → PNG.188+ * Browser: ZXing BitMatrix → OffscreenCanvas → PNG.145189  * Node/test: bwip-js/node → Buffer → PNG.146190  */147191 export async function generateAztecPng(payload: string): Promise<AztecImage> {148192   if (typeof OffscreenCanvas !== "undefined") {149-    return generateAztecPngBrowser(payload);193+    return matrixToPngBrowser(buildAztecMatrix(payload));150194   }151-  return generateAztecPngNode(payload);195+  return matrixToPngNode(payload);152196 }153197 154-// ── Aztec PNG decoding (round-trip) ─────────────────────────────────────────198+// ── Aztec PNG decoding (canvas-based, kept for external callers) ──────────────155199 156200 /**157201  * Decode an Aztec PNG via @zxing. Returns the decoded UTF-8 text, or `null`158202  * if decoding fails for any reason (no DOM, malformed PNG, no match found).159- * Never throws — the caller decides whether a `null` result is a verification160- * failure or a deliberate skip.203+ * Never throws.204+ *205+ * Note: `generateVerifiedAztec` no longer calls this — it uses the in-memory206+ * `verifyMatrixRoundTrip` path instead. This export is kept for tooling that207+ * needs to decode an arbitrary Aztec PNG image.161208  */162209 export async function decodeAztecFromPng(pngBytes: Uint8Array): Promise<string | null> {163-  // The decoder needs raw pixel data, which means we need a canvas to164-  // rasterize the PNG into ImageData. Skip the round-trip in environments165-  // without OffscreenCanvas (vitest with environment: 'node').166210   if (typeof OffscreenCanvas === "undefined" || typeof createImageBitmap === "undefined") {167211     return null;168212   }169213 170214   try {171-    // Copy into a fresh ArrayBuffer-backed view so Blob's typing is satisfied172-    // (the input Uint8Array may be backed by a SharedArrayBuffer in some173-    // bundler typings, which Blob's BlobPart union rejects).174215     const owned = new Uint8Array(pngBytes.byteLength);175216     owned.set(pngBytes);176217     const blob = new Blob([owned], { type: "image/png" });@@ -178,13 +219,11 @@178219     const canvas = new OffscreenCanvas(bitmap.width, bitmap.height);179220     const ctx = canvas.getContext("2d");180221     if (!ctx) return null;181-    // White-fill before drawing so any transparent pixels composite to white.182222     ctx.fillStyle = "#ffffff";183223     ctx.fillRect(0, 0, bitmap.width, bitmap.height);184224     ctx.drawImage(bitmap, 0, 0);185225     const imageData = ctx.getImageData(0, 0, bitmap.width, bitmap.height);186226 187-    // RGBLuminanceSource wants packed 32-bit ARGB values, not raw Uint8 RGBA.188227     const argb = new Int32Array(bitmap.width * bitmap.height);189228     const raw = imageData.data;190229     for (let i = 0, j = 0; i < raw.length; i += 4, j++) {@@ -208,73 +247,87 @@208247   }209248 }210249 211-// ── Verified Aztec generation ───────────────────────────────────────────────250+// ── Verified Aztec generation ─────────────────────────────────────────────────212251 213252 /**214- * Generate the Aztec code for one envelope and confirm it round-trips. The215- * envelope JSON is serialized once and reused as the decode target so any216- * encoding mismatch (e.g. UTF-8 surrogate corruption) is caught immediately.253+ * Generate the Aztec code for one envelope with in-memory round-trip254+ * verification. The verification step is synchronous and DOM-free — it builds255+ * the pixel array directly from the ZXing BitMatrix using256+ * GlobalHistogramBinarizer, so it works identically in the browser popup and257+ * in vitest's node environment (unlike the old canvas-based path which was258+ * silently skipped in node).217259  *218- * In environments where round-trip decoding is unavailable (vitest node), the219- * verification step is skipped — the generator still throws on encoder220- * failure, which is the only condition this path can detect without a DOM.260+ * If the encoder produces a matrix that does not decode back to the envelope261+ * JSON, we throw immediately — no retry. The ZXing encoder is deterministic;262+ * a failure is a hard bug, not a transient error.221263  */222264 export async function generateVerifiedAztec(envelope: ChunkEnvelope): Promise<AztecImage> {223265   const envelopeJson = JSON.stringify(envelope);224266 225-  let image: AztecImage;267+  // Step 1: Encode → BitMatrix (pure ZXing JS, no DOM)268+  let matrix: BitMatrix;226269   try {227-    image = await generateAztecPng(envelopeJson);270+    matrix = buildAztecMatrix(envelopeJson);228271   } catch (err) {229-    if (err instanceof CodexError) throw err;230272     throw new CodexError(231273       "AZTEC_GENERATION_FAILED",232-      `Failed to generate Aztec code for chunk ${envelope.i}: ${err instanceof Error ? err.message : String(err)}`,274+      `AztecEncoder failed for chunk ${envelope.i}: ${err instanceof Error ? err.message : String(err)}`,233275     );234276   }235277 236-  if (!image.pngBytes || image.pngBytes.length < 32) {278+  // Step 2: In-memory round-trip — verify before committing the PNG279+  if (!verifyMatrixRoundTrip(matrix, envelopeJson)) {280+    // Compute a diagnostic diff to aid debugging if this ever fires.281+    let diagSuffix = "";282+    try {283+      const modules = matrix.getWidth();284+      const scale = 4;285+      const pad = 2 * scale;286+      const imgW = modules * scale + pad * 2;287+      const WHITE = -1;288+      const BLACK = (0xff << 24) | 0;289+      const argb = new Int32Array(imgW * imgW);290+      argb.fill(WHITE);291+      for (let y = 0; y < modules; y++)292+        for (let x = 0; x < modules; x++)293+          if (matrix.get(x, y)) {294+            const base = (pad + y * scale) * imgW + pad + x * scale;295+            for (let dy = 0; dy < scale; dy++)296+              for (let dx = 0; dx < scale; dx++)297+                argb[base + dy * imgW + dx] = BLACK;298+          }299+      const source = new RGBLuminanceSource(argb, imgW, imgW);300+      const binarizer = new GlobalHistogramBinarizer(source);301+      const bitmap = new BinaryBitmap(binarizer);302+      const decoded = new AztecCodeReader().decode(bitmap).getText();303+      const el = envelopeJson.length;304+      const dl = decoded.length;305+      let diffAt = -1;306+      for (let k = 0; k < Math.min(el, dl); k++) {307+        if (envelopeJson[k] !== decoded[k]) { diffAt = k; break; }308+      }309+      const ctx = (s: string) => JSON.stringify(s.slice(Math.max(0, diffAt - 8), diffAt + 20));310+      diagSuffix = ` decoded len=${dl} expected len=${el} first diff at ${diffAt}: expected ${ctx(envelopeJson)} got ${ctx(decoded)}`;311+    } catch (diagErr) {312+      diagSuffix = ` (decode threw: ${diagErr instanceof Error ? diagErr.message : String(diagErr)})`;313+    }237314     throw new CodexError(238-      "AZTEC_GENERATION_FAILED",239-      `Aztec PNG for chunk ${envelope.i} was empty`,240-    );241-  }242-243-  // Skip round-trip when we can't rasterize — see decodeAztecFromPng().244-  if (typeof OffscreenCanvas === "undefined" || typeof createImageBitmap === "undefined") {245-    return image;246-  }247-248-  // Retry up to 5 times on any decode failure — break immediately on a249-  // confirmed correct decode. Track the last non-null wrong result so we250-  // can surface diagnostic detail if all attempts fail.251-  let decoded: string | null = null;252-  let lastMismatch: string | null = null;253-  for (let attempt = 0; attempt < 5; attempt++) {254-    const candidate = await decodeAztecFromPng(image.pngBytes);255-    if (candidate === envelopeJson) { decoded = candidate; break; }256-    if (candidate !== null) lastMismatch = candidate;257-  }258-  if (decoded === null && lastMismatch === null) {259-    throw new CodexError(260315       "AZTEC_ROUNDTRIP_FAILED",261-      `Chunk ${envelope.i} generated but cannot be decoded back after 5 attempts. This Codex cannot be trusted.`,316+      `Chunk ${envelope.i}: in-memory round-trip failed.${diagSuffix}`,262317     );263318   }264-  if (decoded === null) {265-    // lastMismatch is non-null — decoded something but wrong content.266-    const el = envelopeJson.length;267-    const dl = lastMismatch!.length;268-    let diffAt = -1;269-    for (let k = 0; k < Math.min(el, dl); k++) {270-      if (envelopeJson[k] !== lastMismatch![k]) { diffAt = k; break; }319+320+  // Step 3: Render to PNG321+  try {322+    if (typeof OffscreenCanvas !== "undefined") {323+      return await matrixToPngBrowser(matrix);271324     }272-    const ctx = (s: string) => JSON.stringify(s.slice(Math.max(0, diffAt - 8), diffAt + 20));325+    return await matrixToPngNode(envelopeJson);326+  } catch (err) {327+    if (err instanceof CodexError) throw err;273328     throw new CodexError(274-      "AZTEC_CONTENT_MISMATCH",275-      `Chunk ${envelope.i}: expected len=${el} decoded len=${dl} first diff at pos ${diffAt}. ` +276-        `expected: ${ctx(envelopeJson)} decoded: ${ctx(lastMismatch!)}`,329+      "AZTEC_GENERATION_FAILED",330+      `PNG render failed for chunk ${envelope.i}: ${err instanceof Error ? err.message : String(err)}`,277331     );278332   }279-  return image;280333 }

@@ -4,6 +4,7 @@44   CodexError,55   computeParityShards,66   STORAGE_KEY_VERIFY_CODE,7+  type ChunkEnvelope,78   type CodexDeps,89 } from "../../shared/codex-types";910 import type { VaultEntry } from "../../shared/types";@@ -19,6 +20,7 @@1920   encodeIntoStripes,2021   encodeWithErasure,2122 } from "./erasure";23+import { buildAztecMatrix, generateVerifiedAztec, verifyMatrixRoundTrip } from "./aztec";2224 import { generateCodex } from "./generate";2325 2426 // ── chrome.storage shim ─────────────────────────────────────────────────────@@ -334,4 +336,95 @@334336       decodeWithErasure(present, stripe.dataShards, stripe.totalChunks),335337     ).rejects.toThrow(CodexError);336338   }, 60_000);339+});340+341+// ── Aztec round-trip verification ─────────────────────────────────────────────342+343+describe("aztec round-trip", () => {344+  beforeEach(() => {345+    installChromeStorageMock();346+  });347+348+  it("buildAztecMatrix + verifyMatrixRoundTrip: 200 varied payloads all pass", () => {349+    // Exercise the core encode→decode path for a wide range of envelope-like350+    // JSON strings. This is fast (synchronous ZXing in-memory, no canvas, no351+    // bwip-js) and covers the payload patterns that previously caused352+    // AZTEC_CONTENT_MISMATCH with HybridBinarizer.353+    for (let i = 0; i < 200; i++) {354+      // Simulate an envelope JSON payload. Use CHUNK_SIZE-sized chunk data with355+      // a per-chunk bit pattern so each payload is unique.356+      const data = new Uint8Array(CHUNK_SIZE);357+      for (let j = 0; j < CHUNK_SIZE; j++) data[j] = ((i * 37 + j * 7) ^ (i << 3)) & 0xff;358+359+      // Build a short envelope-like JSON string resembling the real envelope format.360+      // Base64url encode the chunk data to keep it printable ASCII (matching the361+      // real pipeline which uses bytesToBase64Url).362+      const b64 = btoa(String.fromCharCode(...data.slice(0, 60))).replace(/\+/g, "-").replace(/\//g, "_").replace(/=/g, "");363+      const payload = JSON.stringify({364+        v: 3, i, t: 200, p: i >= 188, c: "PX-TEST-CODE",365+        d: b64,366+        h: "abcdef1234567890abcdef1234567890",367+        s: 0, st: 1,368+      });369+370+      const matrix = buildAztecMatrix(payload);371+      const ok = verifyMatrixRoundTrip(matrix, payload);372+      if (!ok) {373+        throw new Error(`verifyMatrixRoundTrip failed for chunk ${i} (payload len=${payload.length})`);374+      }375+    }376+  });377+378+  it("generateVerifiedAztec: 20 real envelopes survive round-trip", async () => {379+    // End-to-end test of generateVerifiedAztec using real chunk envelopes built380+    // by the same helpers used in the live pipeline. Any AZTEC_ROUNDTRIP_FAILED381+    // or AZTEC_CONTENT_MISMATCH throw will fail the test immediately.382+    const envelopes: ChunkEnvelope[] = [];383+    for (let i = 0; i < 20; i++) {384+      const data = new Uint8Array(CHUNK_SIZE);385+      for (let j = 0; j < CHUNK_SIZE; j++) data[j] = ((i * 53 + j * 11) ^ (i * 19)) & 0xff;386+      envelopes.push(await buildChunkEnvelope(data, i, 20, i >= 17, "PX-RTRP-CODE", 0, 1));387+    }388+389+    for (const env of envelopes) {390+      const img = await generateVerifiedAztec(env);391+      expect(img.pngBytes.length).toBeGreaterThan(0);392+    }393+  }, 120_000);394+395+  it("generateCodex: large vault (100 KB) completes without AZTEC errors", async () => {396+    // A realistic-sized vault that exercises multi-stripe encoding and produces397+    // O(100) Aztec codes. All codes must pass in-memory round-trip verification.398+    installChromeStorageMock();399+400+    // 80 KB of pseudo-random incompressible base64 data → ~100 data shards401+    const alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";402+    let seed = 0xdeadbeef;403+    const chars: string[] = new Array(80_000);404+    for (let i = 0; i < 80_000; i++) {405+      seed = (seed * 1664525 + 1013904223) >>> 0;406+      chars[i] = alphabet[(seed >>> 16) & 0x3f]!;407+    }408+    const slotA = "ENCRYPTED::" + chars.join("");409+410+    const deps: CodexDeps = {411+      getSlotA: async () => slotA,412+      getSlotB: async () => null,413+      getLastModified: async () => "1700000000000",414+      getAllEntries: async () => [415+        { id: "1", title: "GitHub", username: "alice", password: "secret", createdAt: 1, modifiedAt: 2 },416+      ],417+      getVerifyCode: async () => "PX-LARG-TEST",418+      isVaultUnlocked: () => true,419+    };420+421+    const steps: string[] = [];422+    const { pdfBytes, manifest } = await generateCodex(deps, (step) => {423+      if (!steps.includes(step)) steps.push(step);424+    });425+426+    expect(pdfBytes[0]).toBe(0x25); // %PDF427+    expect(manifest.totalChunks).toBeGreaterThan(50);428+    expect(steps).toEqual(["compress", "erasure", "aztec", "verify", "pdf"]);429+  }, 300_000); // 5 min — bwip-js PNG for ~100 chunks dominates in node337430 });