feat(01-08): install ts-ebml + webm-muxer; pin SW-compat via deps test

- Add ts-ebml ^3.0.2 (parse half) and webm-muxer ^5.1.4 (write half) per
  CONTEXT.md amendment D-14-remux; both MIT, both verified SW-compatible
  in the d13 debug-session library survey.
- tests/background/webm-remux-deps.test.ts pins two contracts:
  (a) named exports surface (Muxer + ArrayBufferTarget + Decoder).
  (b) both libraries import cleanly when window/document are absent on
      globalThis — guards the published dist against accidentally
      acquiring DOM globals on the hot path that would crash the
      Chrome service-worker runtime.
- Note: webm-muxer 5.1.4 upstream-deprecated in favor of Mediabunny; the
  pinned version still meets the d13 architectural requirement
  (single-EBML output via addVideoChunkRaw). Migration to Mediabunny is
  out of scope for Plan 01-08 and would require a new ADR.
- Baseline 53 GREEN + 2 new GREEN; tsc clean; 2 webm-playback duration
  RED still pending (drive to GREEN in Tasks 3-5).

package-lock.json

@@ -9,7 +9,9 @@
       "version": "1.0.0",
       "dependencies": {
         "jszip": "^3.10.1",
-        "rrweb": "^2.0.0-alpha.4"
+        "rrweb": "^2.0.0-alpha.4",
+        "ts-ebml": "^3.0.2",
+        "webm-muxer": "^5.1.4"
       },
       "devDependencies": {
         "@crxjs/vite-plugin": "^2.0.0-beta.25",
@@ -1233,6 +1235,12 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/dom-webcodecs": {
+      "version": "0.1.18",
+      "resolved": "https://registry.npmjs.org/@types/dom-webcodecs/-/dom-webcodecs-0.1.18.tgz",
+      "integrity": "sha512-vAvE8C9DGWR+tkb19xyjk1TSUlJ7RUzzp4a9Anu7mwBT+fpyePWK1UxmH14tMO5zHmrnrRIMg5NutnnDztLxgg==",
+      "license": "MIT"
+    },
     "node_modules/@types/estree": {
       "version": "1.0.8",
       "resolved": "https://registry.npmjs.org/@types/estree/-/estree-1.0.8.tgz",
@@ -1264,6 +1272,12 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/wicg-file-system-access": {
+      "version": "2020.9.8",
+      "resolved": "https://registry.npmjs.org/@types/wicg-file-system-access/-/wicg-file-system-access-2020.9.8.tgz",
+      "integrity": "sha512-ggMz8nOygG7d/stpH40WVaNvBwuyYLnrg5Mbyf6bmsj/8+gb6Ei4ZZ9/4PNpcPNTT8th9Q8sM8wYmWGjMWLX/A==",
+      "license": "MIT"
+    },
     "node_modules/@vitest/expect": {
       "version": "4.1.6",
       "resolved": "https://registry.npmjs.org/@vitest/expect/-/expect-4.1.6.tgz",
@@ -1435,6 +1449,14 @@
         "node": ">=8"
       }
     },
+    "node_modules/buffers": {
+      "version": "0.1.1",
+      "resolved": "https://registry.npmjs.org/buffers/-/buffers-0.1.1.tgz",
+      "integrity": "sha512-9q/rDEGSb/Qsvv2qvzIzdluL5k7AaJOTrw23z9reQthrbF7is4CtlT0DXyO1oei2DCp4uojjzQ7igaSHp1kAEQ==",
+      "engines": {
+        "node": ">=0.2.0"
+      }
+    },
     "node_modules/chai": {
       "version": "6.2.2",
       "resolved": "https://registry.npmjs.org/chai/-/chai-6.2.2.tgz",
@@ -1445,6 +1467,15 @@
         "node": ">=18"
       }
     },
+    "node_modules/commander": {
+      "version": "12.1.0",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-12.1.0.tgz",
+      "integrity": "sha512-Vw8qHK3bZM9y/P10u3Vib8o/DdkvA2OtPtZvD871QKjy74Wj1WSKFILMPRPSdUSx5RFK1arlJzEtA4PkFgnbuA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=18"
+      }
+    },
     "node_modules/convert-source-map": {
       "version": "1.9.0",
       "resolved": "https://registry.npmjs.org/convert-source-map/-/convert-source-map-1.9.0.tgz",
@@ -1575,6 +1606,40 @@
         "url": "https://github.com/fb55/domutils?sponsor=1"
       }
     },
+    "node_modules/ebml": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/ebml/-/ebml-3.0.0.tgz",
+      "integrity": "sha512-Q6C1u4/TX1nYipT9HNIopp95YyyyI0zs1GXdNRKO7XL7k+oo+ZtDc1CaJjpCdmlLxWsnlKBOXJCXkYU0K/Anlg==",
+      "license": "MIT",
+      "dependencies": {
+        "buffers": "^0.1.1",
+        "debug": "~3.1.0"
+      },
+      "engines": {
+        "node": ">= 6.4"
+      }
+    },
+    "node_modules/ebml-block": {
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/ebml-block/-/ebml-block-1.1.2.tgz",
+      "integrity": "sha512-HgNlIsRFP6D9VKU5atCeHRJY7XkJP8bOe8yEhd8NB7B3b4++VWTyauz6g650iiPmLfPLGlVpoJmGSgMfXDYusg==",
+      "license": "MIT"
+    },
+    "node_modules/ebml/node_modules/debug": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/debug/-/debug-3.1.0.tgz",
+      "integrity": "sha512-OX8XqP7/1a9cqkxYw2yXss15f26NKWBpDXQd0/uK/KPqdQhxbPa994hnzjcE2VqQpDslf55723cKPUOGSmMY3g==",
+      "license": "MIT",
+      "dependencies": {
+        "ms": "2.0.0"
+      }
+    },
+    "node_modules/ebml/node_modules/ms": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/ms/-/ms-2.0.0.tgz",
+      "integrity": "sha512-Tpp60P6IUJDTuOq/5Z8cdskzJujfwqfOTkrwIwj7IRISpnkJnT6SyJ4PCPnGMoFjC9ddhal5KVIYtAt97ix05A==",
+      "license": "MIT"
+    },
     "node_modules/entities": {
       "version": "4.5.0",
       "resolved": "https://registry.npmjs.org/entities/-/entities-4.5.0.tgz",
@@ -1641,6 +1706,15 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/events": {
+      "version": "3.3.0",
+      "resolved": "https://registry.npmjs.org/events/-/events-3.3.0.tgz",
+      "integrity": "sha512-mQw+2fkQbALzQ7V0MY0IqdnXNOeTtP4r0lN9z7AAawCXgqea7bDii20AYrIBrFd/Hx0M2Ocz6S111CaFkUcb0Q==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=0.8.x"
+      }
+    },
     "node_modules/expect-type": {
       "version": "1.3.0",
       "resolved": "https://registry.npmjs.org/expect-type/-/expect-type-1.3.0.tgz",
@@ -1769,6 +1843,12 @@
       "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
       "license": "ISC"
     },
+    "node_modules/int64-buffer": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/int64-buffer/-/int64-buffer-1.1.0.tgz",
+      "integrity": "sha512-94smTCQOvigN4d/2R/YDjz8YVG0Sufvv2aAh8P5m42gwhCsDAJqnbNOrxJsrADuAFAA69Q/ptGzxvNcNuIJcvw==",
+      "license": "MIT"
+    },
     "node_modules/is-extglob": {
       "version": "2.1.1",
       "resolved": "https://registry.npmjs.org/is-extglob/-/is-extglob-2.1.1.tgz",
@@ -2126,6 +2206,12 @@
         "@jridgewell/sourcemap-codec": "^1.5.5"
       }
     },
+    "node_modules/matroska-schema": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/matroska-schema/-/matroska-schema-2.1.0.tgz",
+      "integrity": "sha512-6c1oFmDxf4Vc5J5lA+9wO7TKcw5M1w85HfzFhAFT4OuEUuqp/s/jqqC3OKlaWe1YwN5wTThJyTC7iwhyW7kQdg==",
+      "license": "MIT"
+    },
     "node_modules/merge2": {
       "version": "1.4.1",
       "resolved": "https://registry.npmjs.org/merge2/-/merge2-1.4.1.tgz",
@@ -2597,6 +2683,23 @@
         "node": ">=8.0"
       }
     },
+    "node_modules/ts-ebml": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/ts-ebml/-/ts-ebml-3.0.2.tgz",
+      "integrity": "sha512-Br6DA/YbdpsiSQjc0KaF3ASQtkk3MCiA4q5kIA7ptv6adZa/MdYa2TXAXF2bAzRZIMWfyFEC9Gicr3nb51MgDA==",
+      "license": "MIT",
+      "dependencies": {
+        "commander": "^12.0.0",
+        "ebml": "^3.0.0",
+        "ebml-block": "^1.1.2",
+        "events": "^3.3.0",
+        "int64-buffer": "^1.0.1",
+        "matroska-schema": "^2.1.0"
+      },
+      "bin": {
+        "ts-ebml": "lib/cli.js"
+      }
+    },
     "node_modules/tslib": {
       "version": "2.8.1",
       "resolved": "https://registry.npmjs.org/tslib/-/tslib-2.8.1.tgz",
@@ -2964,6 +3067,17 @@
         }
       }
     },
+    "node_modules/webm-muxer": {
+      "version": "5.1.4",
+      "resolved": "https://registry.npmjs.org/webm-muxer/-/webm-muxer-5.1.4.tgz",
+      "integrity": "sha512-ditzgFVFbfqPaugkIr4mGhAdob5K9HY6Rzlh7TRsA368yA1sp/m5O7nQCcMLdgFDeNGtFPg8B+MeXLtpzKWX6Q==",
+      "deprecated": "This library is superseded by Mediabunny. Please migrate to it.",
+      "license": "MIT",
+      "dependencies": {
+        "@types/dom-webcodecs": "^0.1.4",
+        "@types/wicg-file-system-access": "^2020.9.5"
+      }
+    },
     "node_modules/why-is-node-running": {
       "version": "2.3.0",
       "resolved": "https://registry.npmjs.org/why-is-node-running/-/why-is-node-running-2.3.0.tgz",

package.json

@@ -10,8 +10,10 @@
     "test": "vitest run"
   },
   "dependencies": {
+    "jszip": "^3.10.1",
     "rrweb": "^2.0.0-alpha.4",
-    "jszip": "^3.10.1"
+    "ts-ebml": "^3.0.2",
+    "webm-muxer": "^5.1.4"
   },
   "devDependencies": {
     "@crxjs/vite-plugin": "^2.0.0-beta.25",
@@ -20,4 +22,4 @@
     "vite": "^5.4.2",
     "vitest": "^4"
   }
-}
+}

tests/background/webm-remux-deps.test.ts

@@ -0,0 +1,137 @@
+// tests/background/webm-remux-deps.test.ts
+//
+// Plan 01-08 Task 1: SW-compatibility + presence contract for the two new
+// runtime dependencies that the WebM remux pipeline rests on. Pins the
+// architectural commitment that landed in CONTEXT.md amendment D-14-remux:
+//   - `ts-ebml`  ^3.0.2 (MIT, parses each VideoSegment's EBML structure)
+//   - `webm-muxer` ^5.1.4 (MIT, writes the single-EBML-headered output)
+//
+// Both libraries were surveyed in `.planning/debug/d13-multi-ebml-concat-
+// unplayable.md` (Evidence/library-survey, lines 380-410). They are pure
+// JS, pure ESM/CJS, and were grep-verified at survey time to contain no
+// hard DOM-global references on the hot path. Chrome's service-worker
+// runtime (where `remuxSegments()` will execute) does not provide
+// `window` or `document`; this test pins that compat at the
+// devDependency-import surface so a future bump that accidentally adds
+// a DOM global is caught at test time rather than at runtime in a
+// production SW.
+//
+// Test 1 asserts named-export presence (RED until `npm install` lands).
+// Test 2 asserts both libraries load under default Node globals without
+// referencing `window` or `document` synchronously at import time.
+//
+// Skip discipline: none — these are pure import-shape tests, no external
+// binaries, no fixtures. Vitest's default Node environment is sufficient.
+
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+
+interface GlobalSnapshot {
+  window: unknown;
+  document: unknown;
+  hadWindow: boolean;
+  hadDocument: boolean;
+}
+
+/**
+ * Capture the current values of `window` and `document` on `globalThis`
+ * so they can be restored after a test that deletes them. Vitest's
+ * `vi.stubGlobal` is not used here because we want to assert the
+ * absence of the globals at import time, not just stub them.
+ *
+ * @returns Snapshot the caller passes back to {@link restoreGlobals}.
+ */
+function snapshotGlobals(): GlobalSnapshot {
+  const g = globalThis as unknown as Record<string, unknown>;
+  return {
+    window: g.window,
+    document: g.document,
+    hadWindow: 'window' in g,
+    hadDocument: 'document' in g,
+  };
+}
+
+/**
+ * Restore the globals captured by {@link snapshotGlobals}. Idempotent.
+ *
+ * @param snap - Snapshot returned by {@link snapshotGlobals}.
+ */
+function restoreGlobals(snap: GlobalSnapshot): void {
+  const g = globalThis as unknown as Record<string, unknown>;
+  if (snap.hadWindow) {
+    g.window = snap.window;
+  } else {
+    delete g.window;
+  }
+  if (snap.hadDocument) {
+    g.document = snap.document;
+  } else {
+    delete g.document;
+  }
+}
+
+describe('webm-remux dependencies (Plan 01-08 Task 1)', () => {
+  it('exports Muxer + ArrayBufferTarget + Decoder', async () => {
+    // Dynamic import so a missing package surfaces as a precise test
+    // failure ("Cannot find module 'webm-muxer'") rather than a Vitest
+    // collection error that hides which dependency is the cause.
+    const webmMuxer = await import('webm-muxer');
+    expect(webmMuxer.Muxer).toBeDefined();
+    expect(webmMuxer.ArrayBufferTarget).toBeDefined();
+
+    const tsEbml = await import('ts-ebml');
+    expect(tsEbml.Decoder).toBeDefined();
+  });
+
+  describe('loads under default Node globals without DOM-global ReferenceErrors', () => {
+    let snap: GlobalSnapshot;
+
+    beforeEach(() => {
+      snap = snapshotGlobals();
+      const g = globalThis as unknown as Record<string, unknown>;
+      delete g.window;
+      delete g.document;
+    });
+
+    afterEach(() => {
+      restoreGlobals(snap);
+    });
+
+    it('webm-muxer + ts-ebml do not throw on import when window/document are absent', async () => {
+      // The Chrome service-worker runtime provides neither `window` nor
+      // `document`. If either library's published dist references one
+      // of these synchronously at module evaluation time (e.g. a UMD
+      // wrapper falling through to `window`), the import below would
+      // throw a ReferenceError and this test would fail with a clear
+      // signal.
+      //
+      // ts-ebml's UMD wrapper does contain a `typeof window` check
+      // with a `self`/`global` fallback per the d13 library survey
+      // — `typeof` does NOT throw on undeclared identifiers per
+      // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/typeof
+      // so the fallback path resolves cleanly.
+      //
+      // webm-muxer is documented zero-DOM-ref.
+      let webmMuxerError: unknown = null;
+      try {
+        await import('webm-muxer');
+      } catch (e) {
+        webmMuxerError = e;
+      }
+      expect(
+        webmMuxerError,
+        `webm-muxer threw at import time without window/document: ${String(webmMuxerError)}`,
+      ).toBeNull();
+
+      let tsEbmlError: unknown = null;
+      try {
+        await import('ts-ebml');
+      } catch (e) {
+        tsEbmlError = e;
+      }
+      expect(
+        tsEbmlError,
+        `ts-ebml threw at import time without window/document: ${String(tsEbmlError)}`,
+      ).toBeNull();
+    });
+  });
+});