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/health.ts

@@ -1,10 +1,19 @@
 import { Elysia } from "elysia"
 
-export const healthRoutes = new Elysia({ prefix: "/health" }).get(
+export const healthRoutes = new Elysia({
+  prefix: "/health",
+  detail: { tags: ["Health"] },
+}).get(
   "/",
   () => ({
     status: "ok",
     timestamp: new Date().toISOString(),
     service: "deckyvault-api",
   }),
+  {
+    detail: {
+      summary: "Health check",
+      description: "Returns the current health status of the API.",
+    },
+  },
 )