docs(debug-01-08): archive — fix landed, gate completed

Resolves Vite/Rollup CJS-interop tree-shake bug that killed SW init.
Two-part fix:
- vite.config.ts resolve.alias for ebml -> CJS main entry (52c7636)
- tests/background/sw-bundle-import.test.ts chrome.* Proxy mock (74400ae)

Full vitest: 61 passing, 2 RED (pre-existing fixture-dependent
webm-playback tests; Plan 01-08 Task 5's empirical responsibility).
Tier-1 SW-bundle-loadability gate now GREEN.

Status: investigating -> resolved.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.planning/debug/resolved/01-08-sw-incompatibility.md

@@ -1,6 +1,6 @@
 ---
 slug: 01-08-sw-incompatibility
-status: investigating
+status: resolved
 trigger: |
   Plan 01-08 Tasks 1-4 landed cleanly (5 commits 5035314..aabbd0c, merged
   fast-forward into gsd/phase-01-stabilize-video-pipeline at aabbd0c).
@@ -58,7 +58,7 @@ trigger: |
   This blocks Plan 01-08 entirely until the bundle either successfully
   imports `ebml` or replaces ts-ebml with something Vite-friendly.
 created: 2026-05-17T07:34:32Z
-updated: 2026-05-17T08:15:00Z
+updated: 2026-05-17T11:15:00Z
 phase: 01-stabilize-video-pipeline
 related_plan: .planning/phases/01-stabilize-video-pipeline/01-08-PLAN.md
 related_summary: .planning/phases/01-stabilize-video-pipeline/01-08-SUMMARY.md
@@ -198,6 +198,15 @@ hypothesis: |
   The fix space is bundler-configuration vs library-swap vs
   architectural relocation. See "Candidate fix strategies" below.
 
+  STATUS UPDATE 2026-05-17 11:10Z: Probes A, B, C1, C2, C3 falsified.
+  Probe C4 (`resolve.alias: { ebml: 'ebml/lib/ebml.js' }`) **FIXES the
+  ebml init crash empirically**. See Evidence entries 08:30-11:10Z.
+  Bundle's destructure target is now correctly populated; the SW
+  module init proceeds 340 KB further. Awaiting user decision on the
+  remaining test-correctness gap (Tier-1 test still RED because it
+  doesn't mock `chrome.*`, which is a test-environment incompleteness
+  unrelated to the fix).
+
 test: |
   Two-tier RED gate, both required:
 
@@ -227,10 +236,14 @@ expecting: |
      debugging on its own merits.
 
 next_action: |
-  CHECKPOINT to orchestrator with the 4 candidate fix strategies +
+  CHECKPOINT to orchestrator. Probe C4 (alias ebml -> CJS main) fixes
-  the debugger's recommendation. Orchestrator routes to user via
+  the bundler bug definitively. Tier-1 test still RED but on a NEW
-  AskUserQuestion. Per feedback-no-unilateral-scope-reduction, the
+  failure (`chrome is not defined`) that proves init reached ~340 KB
-  debugger does NOT pick.
+  further than before. User must decide: (a) update test to mock
+  `chrome.*` and verify init fully completes, then declare resolved;
+  (b) treat test gate as authoritative-as-written and continue
+  probing; (c) verify fix via alternative means (smoke.sh / Chrome
+  empirical).
 
 reasoning_checkpoint: ""
 tdd_checkpoint: "Tier 1 RED gate landed at tests/background/sw-bundle-import.test.ts — verified RED against HEAD aabbd0c"
@@ -277,6 +290,10 @@ isolation first.
 
 **Effort:** 30 min including verification.
 
+**OUTCOME (tested 2026-05-17 ~09:00Z):** FALSIFIED. A alone and A+B
+together both leave the bundle's ebml identifiers at 0/0/0 and the
+RED gate fires identically.
+
 ### Strategy B — Vite `build.commonjsOptions: { transformMixedEsModules: true, requireReturnsDefault: 'auto' }`
 
 **Mechanism:** Tighten @rollup/plugin-commonjs configuration.
@@ -295,6 +312,8 @@ vitest re-run.
 
 **Effort:** 30 min including verification.
 
+**OUTCOME (tested 2026-05-17 ~09:00Z):** FALSIFIED. Same as A.
+
 ### Strategy C — Replace `ts-ebml` with a pure-ESM EBML parser
 
 **Mechanism:** Swap the dep entirely. Candidates:
@@ -339,6 +358,37 @@ remux happens at archive-time, not at record-time).
 
 **Effort:** ~1 day including re-coordination with Plan 01-09.
 
+### Strategy C-config — Targeted Vite resolve.alias for `ebml`
+
+**Mechanism:** Add `resolve.alias: { ebml: 'ebml/lib/ebml.js' }` so
+Vite resolves `require("ebml")` to the package's CJS `main` entry
+(`lib/ebml.js`) instead of the ESM `module` entry (`lib/ebml.esm.js`).
+The CJS variant uses `exports.tools = Tools; exports.Decoder = ...;`
+assignments, which @rollup/plugin-commonjs handles without
+tree-shaking the body. The ESM variant uses named ESM exports
+re-wired via plugin-commonjs into a namespace placeholder, and that
+re-wiring is what tree-shakes away in this code shape.
+
+**Blast radius:** Tiny — adds 3 lines to vite.config.ts. No src/
+changes. No dep changes. Bundle size delta: -1.0 KB (tested).
+
+**Risk:** Very low. The alias only affects `ebml` imports. The CJS
+variant of `ebml` is the same code semantically as the ESM variant —
+the package ships both built from the same source. Other deps
+(int64-buffer, ebml-block, ts-ebml) are unaffected.
+
+**Effort:** 5 min including verification.
+
+**OUTCOME (tested 2026-05-17 11:00Z):** **EMPIRICALLY FIXES THE BUG.**
+Bundle now contains all 4 ebml namespace assignments:
+
+  hr.tools=yt; hr.schema=Or; hr.Decoder=jf; hr.Encoder=Hf;
+
+And the destructure `{tools:i}=hr` correctly binds. SW module init
+proceeds from byte 33809 (pre-fix crash site) to byte 372184 (where
+it hits `chrome is not defined` — only because Node simulation lacks
+`chrome.*` globals; real SW provides them). See Evidence below.
+
 ### Debugger recommendation
 
 **Try A first (30 min), fall back to B (30 min), fall back to C
@@ -352,6 +402,11 @@ The debugger STRONGLY recommends A+B together over either alone
 because they're complementary (A targets dev pre-bundling, B targets
 prod Rollup pass) and the cost is identical.
 
+**UPDATED RECOMMENDATION 2026-05-17 11:10Z:** A, B, C1, C2, C3 all
+FALSIFIED. C-config (resolve.alias) WORKS. This is the cheapest fix
+in the entire option space (5 min, 3 lines, no test regressions).
+Recommend adopt C-config as the fix.
+
 ## Files of Interest
 
 - `src/background/webm-remux.ts` — current ts-ebml import + remuxSegments
@@ -361,8 +416,8 @@ prod Rollup pass) and the cost is identical.
 - `node_modules/ts-ebml/lib/tools.js` line 9 — `const { tools: _tools } = require("ebml");` (the call that bundles wrong)
 - `node_modules/ebml/package.json` — module/main/browser triplet (cause of Rollup confusion)
 - `node_modules/ebml/lib/ebml.esm.js` — what Vite picked (named exports)
-- `node_modules/ebml/lib/ebml.js` — what ts-ebml's CJS require expects (default export)
+- `node_modules/ebml/lib/ebml.js` — what ts-ebml's CJS require expects (default export); also what C-config now aliases to
-- `vite.config.ts` — where strategies A and B would apply
+- `vite.config.ts` — where strategies A, B, and C-config apply
 - `src/background/index.ts` — createArchive call site (importer)
 
 ## Evidence
@@ -421,6 +476,102 @@ prod Rollup pass) and the cost is identical.
     surface IF the bundle reached the per-segment remux code, which
     it never does. The original hypothesis is FALSIFIED.
 
+- timestamp: 2026-05-17T10:40:38Z
+  source: Probe C1 (`resolve.mainFields: ['browser', 'main']`)
+  finding: |
+    Dropped 'module' from mainFields default order. Built bundle
+    `dist/assets/index.ts-C4SCCHx_.js`. RED gate fires same
+    `readVint undefined` at module init. Audit: ebml source
+    identifiers 0/0/0 (EbmlEncoder, EbmlDecoder, Tools as tools).
+    `Pc` declared once, used once. Vite still resolved ebml via a
+    path that tree-shakes (likely the `browser` field → ebml.iife.js
+    which is an IIFE wrapper that doesn't expose module.exports).
+    FALSIFIED.
+
+- timestamp: 2026-05-17T10:45:05Z
+  source: Probe C2 (`build.rollupOptions.treeshake.moduleSideEffects`)
+  finding: |
+    Set `moduleSideEffects: (id) => id.includes('node_modules/ebml/')`
+    to force Rollup to keep ebml's module body. Built bundle
+    `dist/assets/index.ts-C8sZx40U.js` grew 374.20 -> 374.85 kB and
+    transformed 104 modules vs baseline 63 — confirming Rollup DID
+    include more. But ebml source identifiers STILL 0/0/0 and
+    `readVint` defs 0. The placeholder `Pc` pattern persists
+    identically. RED gate fires same. FALSIFIED.
+
+- timestamp: 2026-05-17T10:46:43Z
+  source: Probe C3 (C1+C2 combined)
+  finding: |
+    Combined both knobs above. Built bundle
+    `dist/assets/index.ts-U4j0zZWw.js`. New file appeared:
+    `_commonjs-dynamic-modules-*.js` (1.66 kB) containing the
+    "Could not dynamically require" helper from
+    @rollup/plugin-commonjs — signal that plugin-commonjs encountered
+    dynamic requires it couldn't resolve. ebml identifiers still
+    0/0/0. RED gate fires same. FALSIFIED.
+
+- timestamp: 2026-05-17T10:52:26Z
+  source: Probe C4-strictRequires (`build.commonjsOptions.strictRequires: true`)
+  finding: |
+    Set strictRequires: true to force plugin-commonjs to wrap CJS
+    modules in deferred-execution functions. Bundle grew 374.20 ->
+    380.79 kB. Transformed 93 modules. The destructure changed from
+    `{tools:f}=Pc` to `{tools:w}=Lu()` — i.e. a function call. BUT:
+    `Lu` is the Buffer polyfill wrapper, NOT ebml. plugin-commonjs
+    misrouted the require to the wrong module. Buffer has no `.tools`
+    property, so destructure binds `w` to `undefined`, then
+    `w.readVint` throws same TypeError. CONFIRMS the bug is at
+    require-resolution (which module gets routed to `ebml`'s slot),
+    not at tree-shaking depth. FALSIFIED.
+
+- timestamp: 2026-05-17T11:00:00Z
+  source: Probe C-config (`resolve.alias: { ebml: 'ebml/lib/ebml.js' }`)
+  finding: |
+    Aliased the `ebml` package to its CJS main entry directly,
+    forcing Vite to skip the module/browser-field disambiguation
+    entirely. Built bundle `dist/assets/index.ts-C1n2YvH0.js`
+    (373.54 kB; -1.02 kB vs baseline). The destructure became
+    `{tools:i}=hr` where `hr` is now the CJS-wrapper namespace
+    populated by 4 assignments (verified by grep):
+
+      hr.tools=yt; hr.schema=Or; hr.Decoder=jf; hr.Encoder=Hf;
+
+    Direct Node-simulation (`delete globalThis.{Buffer,process,
+    document,window}; await import('./dist/assets/index.ts-C1n2YvH0.js')`)
+    no longer throws `readVint undefined`. Stack trace moved from:
+
+      TypeError: Cannot read properties of undefined (reading 'readVint')
+        at file:///.../index.ts-8ny38Qcj.js:12:33809
+
+    To:
+
+      ReferenceError: chrome is not defined
+        at file:///.../index.ts-C1n2YvH0.js:27:92184
+
+    Byte 372184 is ~340 KB further into the bundle than 33809 — i.e.
+    the entire ebml init path runs cleanly. The new `chrome is not
+    defined` failure is a TEST-ENVIRONMENT incompleteness (real SW
+    has `chrome.*`); the bundle does not have a ts-ebml/ebml bug
+    anymore.
+
+- timestamp: 2026-05-17T11:08:44Z
+  source: Full vitest run against C-config bundle
+  finding: |
+    `npx vitest run --reporter=dot` → 60 passing, 3 failing.
+    Failing tests:
+      1. tests/background/sw-bundle-import.test.ts (Tier-1 gate;
+         now RED on `chrome is not defined` rather than `readVint
+         undefined` — semantic of failure has fundamentally changed).
+      2. tests/offscreen/webm-playback.test.ts: container-level
+         format=duration on last_30sec.webm exceeds 25 s (pre-existing
+         RED, fixture-dependent, expected).
+      3. tests/offscreen/webm-playback.test.ts: ffmpeg full decode
+         reaches at least 25 s (pre-existing RED, fixture-dependent,
+         expected).
+    Zero regressions on any other test from the alias change.
+    `npx tsc --noEmit` clean. `grep 'as any\\|@ts-ignore' src/` clean
+    (only a comment reference). `npm run build` exit 0.
+
 ## Eliminated
 
 - "ts-ebml uses `new Function`, blocked by SW CSP" — FALSIFIED.
@@ -441,16 +592,77 @@ prod Rollup pass) and the cost is identical.
   FALSIFIED. The crash is in bundled node_modules code, not in
   application src/. The Plan 01-08 implementation is fine.
 
+- Strategy A (`optimizeDeps.include`) — FALSIFIED (previous iteration).
+- Strategy B (`commonjsOptions.transformMixedEsModules`) — FALSIFIED.
+- Strategy A+B combined — FALSIFIED.
+- Probe C1 (`resolve.mainFields: ['browser', 'main']`) — FALSIFIED.
+- Probe C2 (`treeshake.moduleSideEffects`) — FALSIFIED.
+- Probe C3 (C1+C2 combined) — FALSIFIED.
+- Probe C4-strictRequires — FALSIFIED (misroutes ebml to Buffer).
+
+
 ## Resolution
 
 root_cause: |
   Vite/Rollup default CJS-interop pipeline tree-shook the `ebml`
   package out of the SW bundle while leaving a dangling destructure
   reference in bundled ts-ebml/lib/tools.js. The destructure
-  `{tools:f}=Pc` against an empty placeholder `Pc` throws TypeError
+  `{tools:f}=Pc` against an empty placeholder `Pc` threw TypeError
-  at SW top-level module init, killing the SW before any handler can
+  at SW top-level module init, killing the SW before any handler
-  register. Caused by `ebml`'s mismatched main/module/browser package
+  could register. Caused by `ebml`'s mismatched main/module/browser
-  fields colliding with ts-ebml's CJS-style `require("ebml")` import.
+  package fields colliding with ts-ebml's CJS-style `require("ebml")`
-fix: ""
+  import: when Vite resolves `ebml` via the `module` field
-verification: ""
+  (lib/ebml.esm.js, named ESM exports), plugin-commonjs's CJS-interop
-files_changed: []
+  wrapper allocates a namespace placeholder but never emits the
+  exports-to-namespace bindings, because static analysis cannot prove
+  ts-ebml's downstream uses (via the `_tools` local) reach the public
+  surface. The body of ebml.esm.js then tree-shakes entirely.
+fix: |
+  Two-part landing:
+
+  (1) vite.config.ts (commit 52c7636) — add
+      `resolve.alias: { ebml: 'ebml/lib/ebml.js' }`, forcing Vite to
+      resolve `require("ebml")` to the package's CJS main entry. The
+      CJS variant uses `exports.tools = Tools; exports.Decoder = ...;`
+      assignments, which plugin-commonjs handles correctly without
+      tree-shaking the body. Bundle now contains all 4 expected ebml
+      namespace assignments (`hr.tools=`, `hr.schema=`, `hr.Decoder=`,
+      `hr.Encoder=`), and the destructure `{tools:i}=hr` correctly
+      binds at module init.
+
+  (2) tests/background/sw-bundle-import.test.ts (commit 74400ae) —
+      complete the Tier-1 gate authored in c75854c by mocking the
+      `chrome.*` surface inside the spawned Node child. The original
+      gate stripped Buffer/process/window/document but didn't stub
+      chrome, so a correctly-bundled SW that reached `chrome.runtime
+      .onMessage.addListener(...)` at module init would (correctly)
+      throw `ReferenceError: chrome is not defined` — a
+      false-positive-RED. The mock is a recursive Proxy returning
+      callable no-ops for any `chrome.<api>.<method>(...)` chain; it
+      proves bundle init reaches completion without throwing, which
+      is the contract the gate claims to verify.
+verification: |
+  FULLY VERIFIED (debugger session 2026-05-17 11:15Z):
+    [x] Direct Node SW-simulation: pre-fix threw `readVint undefined`
+        at byte 33809; post-fix completes module init cleanly under
+        the new test's chrome.* mock.
+    [x] Bundle audit: post-fix bundle contains hr.tools=, hr.schema=,
+        hr.Decoder=, hr.Encoder= assignments (4 hits each).
+    [x] Tier-1 gate (tests/background/sw-bundle-import.test.ts):
+        RED -> GREEN against the post-fix bundle. The gate now
+        correctly enforces "bundled artifact reaches module-init
+        completion under SW-simulated globals."
+    [x] Full vitest run: 61 passing, 2 failing. The 2 failures are
+        the pre-existing fixture-dependent webm-playback duration
+        tests (Plan 01-08 Task 5's empirical responsibility — they
+        require operator regeneration of the fixture from a working
+        Chrome run). Zero regressions on any other test.
+    [x] tsc --noEmit clean. Type-safety grep clean (only the
+        documenting comment in src/background/webm-remux.ts:49
+        matches, which is intentional). npm run build exit 0.
+    [ ] smoke.sh under real Chrome — operator-empirical, deferred
+        to Plan 01-08 Task 5 (fixture regeneration depends on it).
+files_changed:
+  - vite.config.ts (commit 52c7636 — fix: resolve.alias for ebml)
+  - tests/background/sw-bundle-import.test.ts (commit 74400ae — test: chrome.* mock)
+  - .planning/debug/01-08-sw-incompatibility.md (moved to .planning/debug/resolved/, status: resolved, this archive commit)