Kann ich Snapchat vibecoden?

Build me a private ephemeral photo-messaging app, snaps for one friend group that opts in. Requirements:

- Node 22 + Fastify + better-sqlite3, and a vanilla-JS installable PWA served from
  /public with no build step: manifest, service worker, an offline shell that caches
  the UI but never caches snaps.
- Core loop: open the camera with getUserMedia, capture a photo, type or draw a
  caption overlay on a canvas, send it to one or more friends.
- A snap is viewable exactly once for up to 10 seconds; the server deletes the image
  file immediately after the view and keeps only a minimal sent/opened log row.
- Accounts are invite-code only: the admin seeds codes with a CLI script, signup is
  username plus passcode, sessions are httpOnly cookies.
- Per-pair daily streaks tracked server-side, shown next to each friend.
- Group stories: a snap posted to my story is visible to all members and hard-deleted
  after 24 hours by a sweep job.
- Media lives as files on disk outside the web root; metadata in SQLite with WAL mode.
- Web push for new snaps behind a permission prompt; the app must work fully without
  it, and the README says iOS web push is best-effort. VAPID keys and session secret
  in .env, with a documented script that generates them and a .env.example.
- HTTPS is required for camera and push: document local dev with a self-signed cert
  and production behind Caddy on a cheap VPS.
- Be honest in the UI: label view-once as deleted from our server, and state plainly
  that screenshots cannot be detected on the web.
- Tests for delete-after-view, the 24-hour story sweep, and streak day-boundary math
  with a fake clock.
- Out of scope: AR lenses and face filters, Snap Map, Discover or Spotlight feeds,
  video calls, screenshot detection, analytics, and third-party auth.
- README: setup, deploying, where data lives, how deletion actually works, and how
  to invite the first two friends.

Antworte mir auf Deutsch. Oberfläche, Kommentare und README auf Deutsch, alle Bezeichner wie Tabellen, Spalten, Variablen, Routen und Dateinamen bleiben Englisch.