chore: add pre-commit hooks, tighten ESLint, activate Sentry DSN, publish CI coverage (Phase 1)

- Install husky v9 + lint-staged: pre-commit runs eslint --fix and prettier on staged files
- Tighten ESLint base config: no-console→error, ban-ts-comment (ts-ignore banned, ts-expect-error with description allowed), reportUnusedDisableDirectives→error
- Migrate web app from deprecated `next lint` to `eslint src/` with flat config and react-hooks plugin
- Convert all 5 @ts-ignore to @ts-expect-error with descriptions, remove stale disable comments
- Add NEXT_PUBLIC_SENTRY_DSN to docker-compose.prod.yml and .env.example
- Add coverage artifact upload step to CI test job
- Pre-existing violations (102 warnings) downgraded to warn in web config for Phase 2 cleanup

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -198,6 +198,20 @@ jobs:
           pnpm --filter @capakraken/shared exec vitest run --coverage
           pnpm --filter @capakraken/db test:unit
 
+      - name: Upload coverage reports
+        uses: actions/upload-artifact@v4
+        if: ${{ !cancelled() }}
+        with:
+          name: coverage-reports
+          path: |
+            apps/web/coverage/
+            packages/engine/coverage/
+            packages/staffing/coverage/
+            packages/api/coverage/
+            packages/application/coverage/
+            packages/shared/coverage/
+          retention-days: 14
+
   # ──────────────────────────────────────────────
   # Build — depends on typecheck passing
   # ──────────────────────────────────────────────