Kann ich Subclip vibecoden?

Build me the closest honest personal substitute for Subclip, not a platform clone. Requirements:

- Use Python 3.12 + FastAPI for a localhost web app, with a plain JavaScript frontend,
  FFmpeg for media work, and faster-whisper for word-level transcription.
- I can import MP4, MOV, WebM, MP3, or WAV files, see a synced transcript beside the
  video preview, and click any word to seek to its timestamp.
- Deleting transcript ranges creates an undoable cut list. Detect silences longer than
  500 ms and let me accept or reject each suggested cut before rendering.
- Let me edit subtitle text and timing, import or export SRT, and apply one ASS style
  file with font, colors, outline, position, and words-per-line controls.
- Export MP4 in 16:9, 9:16, or 1:1 with center-crop or blur-pad. Never overwrite the
  source, and show FFmpeg progress plus a useful failure message.
- Store projects as JSON under ~/SubclipDIY/projects and renders under
  ~/SubclipDIY/exports, with a recent-projects page and a delete-project action.
- Bind to localhost only. No accounts, uploads, telemetry, or network calls after the
  faster-whisper model has been downloaded.
- Deliberately exclude ONNX models in the browser, Remotion client or server rendering,
  native apps, cloud dubbing, render queues, publishing, an MCP server, and public APIs.
- Add unit tests for cut-list merging and subtitle grouping, plus one smoke test that
  imports a short fixture and produces a playable MP4.
- Include a README with setup for Python and FFmpeg, model-size guidance, data paths,
  supported formats, and an honest warning about CPU transcription and render speed.

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