Fix CSP blocking IPC/assets + fix pyannote AudioDecoder crash

CSP: Add connect-src for ipc.localhost and asset.localhost so Tauri IPC
commands and local file loading (waveform, audio playback) work.

pyannote: Block torchcodec in sys.modules at startup so pyannote.audio
falls back to torchaudio for audio decoding. pyannote has a bug where
it uses AudioDecoder unconditionally even when torchcodec import fails.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src-tauri/tauri.conf.json

@@ -22,7 +22,7 @@
       }
     ],
     "security": {
-      "csp": "default-src 'self'; img-src 'self' asset: https://asset.localhost; media-src 'self' asset: https://asset.localhost; style-src 'self' 'unsafe-inline'",
+      "csp": "default-src 'self'; connect-src ipc: http://ipc.localhost http://asset.localhost https://asset.localhost; img-src 'self' asset: http://asset.localhost https://asset.localhost; media-src 'self' asset: http://asset.localhost https://asset.localhost; style-src 'self' 'unsafe-inline'",
       "assetProtocol": {
         "enable": true,
         "scope": ["**"]