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>

package.json

@@ -33,11 +33,14 @@
     "db:import:dispo": "pnpm --filter @capakraken/db db:import:dispo",
     "db:readiness:demand-assignment": "pnpm --filter @capakraken/db db:readiness:demand-assignment",
     "format": "prettier --write \"**/*.{ts,tsx,md,json}\"",
-    "typecheck": "node ./scripts/run-from-workspace-root.mjs turbo typecheck"
+    "typecheck": "node ./scripts/run-from-workspace-root.mjs turbo typecheck",
+    "prepare": "husky"
   },
   "devDependencies": {
     "@capakraken/eslint-config": "workspace:*",
     "@capakraken/tsconfig": "workspace:*",
+    "husky": "^9.1.7",
+    "lint-staged": "^16.4.0",
     "prettier": "^3.3.3",
     "turbo": "^2.3.3",
     "typescript": "^5.6.3"