Fix Docker deployment and add Tailscale Funnel support

- Fix argon2 native module build in Docker (add build-essential, python3)
- Switch Docker base image from Alpine to Debian-slim for OpenSSL compatibility
- Fix session cookies for HTTP access (COOKIE_SECURE env var)
- Fix TypeScript type errors in sync routes and middleware
- Fix CSS circular dependency in globals.css
- Fix Map iteration in rate-limit cleanup
- Add createdAt field to LocalNote interface
- Configure Tailscale Funnel on port 10000
- Update NEXT_PUBLIC_APP_URL for public funnel access
- Add initial Prisma migration

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/lib/sync/manager.ts

@@ -364,6 +364,7 @@ export async function createLocalNote(
   data: { type: 'QUESTION' | 'GENERAL'; content: string }
 ): Promise<LocalNote> {
   const id = generateTempId()
+  const now = new Date().toISOString()
   const note: LocalNote = {
     id,
     workspaceId,
@@ -372,7 +373,8 @@ export async function createLocalNote(
     askedAt: null,
     deletedAt: null,
     version: 1,
-    syncedAt: new Date().toISOString(),
+    syncedAt: now,
+    createdAt: now,
   }
 
   await db.notes.add(note)