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

lib/api/profile-photo.ts

@@ -29,7 +29,7 @@ function validateMagicBytes(buffer: Buffer, declaredMime: string): boolean {
   return expected.every((byte, i) => buffer[i] === byte)
 }
 
-export const profilePhotoRoutes = new Elysia({ prefix: "/user" })
+export const profilePhotoRoutes = new Elysia({ prefix: "/user", detail: { tags: ["Users"] } })
 
   // ── Upload Profile Photo ──────────────────────────────────────────
   .post(