feat: add OpenAPI support and in-process cron scheduler

- Install @elysia/openapi to auto-generate API docs at /api/openapi
- Install @elysia/cron for in-process scheduled jobs (orphan detection at 2am, storage cleanup at 3am)
- Add Scalar UI docs with 14 tag groups and Bearer JWT security scheme
- Add route-level detail annotations (tags, summaries) to all 30+ route files
- Upgrade crud-builder to accept optional tags config
- Keep HTTP cron endpoint as manual/admin fallback

next.config.ts

@@ -7,7 +7,7 @@ const nextConfig: NextConfig = {
     NEXT_PUBLIC_APP_VERSION: version,
   },
   // Elysia is Bun-native and must not be bundled by Next.js
-  serverExternalPackages: ["elysia", "@elysiajs/eden"],
+  serverExternalPackages: ["elysia", "@elysiajs/eden", "@elysia/openapi", "@elysia/cron"],
   images: {
     remotePatterns: [
       {