fix(infra): plug operational defaults — pg restart, proxy timeout, env template (0.87.1)

Three operational gaps tripped a recent review:

1. **Postgres had no `restart:` policy.** tor / docker-socket-proxy /
   vision-manager all set `unless-stopped`; pg was the lone exception.
   A transient OOM or panic left backend's `depends_on: service_healthy`
   blocking every future restart and took the stack offline. Add
   `unless-stopped` on postgres and on backend/frontend in the base
   compose so the prod overlay is the same shape.

2. **`BACKEND_PROXY_TIMEOUT_MS` was documented but silently a no-op.**
   `.env.example` carried it but `docker-compose.yml` never forwarded it
   into the frontend service env, so the value never reached
   `hooks.server.ts`. Wire it through.

3. **`.env.example` omitted required env vars.** Operators copying the
   template got no admin bootstrap, no boot-seed crawler URL, no
   analysis configuration. Add: `ADMIN_USERNAME`, `ADMIN_PASSWORD`,
   `PRIVATE_MODE`, `ALLOW_SELF_REGISTER`, `CRAWLER_START_URL`,
   `CRAWLER_CDN_HOST`, `ANALYSIS_ENABLED`, `ANALYSIS_VISION_URL`,
   `ANALYSIS_VISION_MODEL`, `ANALYSIS_WORKERS`,
   `ANALYSIS_JOB_TIMEOUT_SECS`, `ANALYSIS_API_KEY` — each with the
   comment block that explains seed-vs-runtime semantics.

Also adds `frontend/vite.config.ts.timestamp-*.mjs` to `.gitignore` — a
crashed dev server leaves these transient files behind otherwise.

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

.gitignore

@@ -8,6 +8,10 @@
 /frontend/build
 /frontend/test-results
 /frontend/playwright-report
+# Vite writes these transient files next to vite.config.ts while the dev
+# server is running, then deletes them on clean shutdown — but a crashed
+# server leaves them behind. Keep them out of `git status` either way.
+/frontend/vite.config.ts.timestamp-*.mjs
 
 # Local storage volume (manga files). `/data` is the root path the
 # compose volume mounts at; `/backend/data` is where the dev backend