fix(01-12): brand polish — replace stale 'AI Call Recorder' refs with Mokosh (4 files)

Plan 01-12 D-07 (commit 5efc2a8) migrated manifest.json:name + tooltip
+ extName/extDesc keys to chrome.i18n placeholders + _locales/{en,ru}/
messages.json resolving to 'Mokosh — Session Capture' (EN) / 'Mokosh —
Запись сессии' (RU). However, 4 trailing references to the pre-D-07
literal 'AI Call Recorder' in non-manifest content surfaces were never
propagated. Operator noticed during Plan 01-10 cycle-2 UAT 2026-05-20.

This commit applies the user-approved 4-file surgical rename:

  - src/welcome/copy.ts: welcome.body.cta.toolbar RU CTA
    "иконку AI Call Recorder" → "иконку Mokosh" (matches toolbar tooltip
    i18n key tooltipOff = "Mokosh — щёлкните, чтобы начать запись").
    Inline rationale comment added cross-ref'ing the i18n key + this
    debug session.

  - README.md: H1 + first paragraph rewritten to
    "# Mokosh — Session Capture" + EN tagline line. Rest of README body
    preserved verbatim (technical-stack section historical mentions
    left as project history, not brand surface).

  - package.json: name "ai-call-extension" → "mokosh-session-capture",
    description rewritten to "Mokosh — Session Capture: Chrome MV3
    extension for operator session recording." version, scripts,
    dependencies, devDependencies untouched.

  - tests/i18n/manifest-i18n.test.ts: header comment block rewritten to
    label the "AI Call Recorder" string as Wave-0 historical state +
    describe the post-D-07 regression-pin role. Test bodies + assertions
    unchanged (already pin the post-D-07 canonical state).

Preservation rationale: .planning/intel/* (brand-decisions-v1.md D-07,
design-system.md, brand-identity.md, classifications/README-*.json,
design-incoming/system/bundle/mokosh-handoff/handoff.html) is audit
trail documenting the "why" of D-07 — kept verbatim. _locales/{en,ru}/
messages.json and manifest.json already post-D-07 canonical — untouched.

Acceptance gates (all PASS 2026-05-20):
  - Empirical grep src/ tests/ README.md package.json: ZERO non-historical
    "AI Call Recorder" matches (only the labeled audit anchor in
    tests/i18n/manifest-i18n.test.ts:8).
  - npx tsc --noEmit: clean.
  - npm run build: ✓ built in 5.29s.
  - npx vitest run tests/i18n/manifest-i18n.test.ts: 10/10 GREEN.
  - npx vitest run tests/background/no-test-hooks-in-prod-bundle.test.ts
    (Tier-1 hook-string grep gate): 13/13 GREEN; FORBIDDEN_HOOK_STRINGS
    list intact.
  - npm test: 151/153 (2 pre-existing ffprobe/ffmpeg timeout flakes in
    webm-remux + webm-playback — verified identical to pristine HEAD
    a2dfc8c via git stash baseline; unrelated to rename).
  - npm run test:uat: 24/24 GREEN.
  - Production bundle grep dist/: ZERO "AI Call Recorder" + ZERO
    "ai-call-extension" matches.

Unblocks Plan 01-10 closure + Phase 1 final closure (REQUIREMENTS /
ROADMAP / STATE marker flip).

Debug record: .planning/debug/resolved/01-12-stale-ai-call-recorder-references.md

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

README.md

@@ -1,4 +1,6 @@
-# AI Call Recorder - Браузерное расширение для записи сессий операторов
+# Mokosh — Session Capture
+
+Chrome MV3 extension that records operator sessions for bug reports.
 
 Фаза 1 — Локальная запись + экспорт архива