fix: meeting stream reconnect on session expiry + onnx worker packaging

[xAlcahest]

Summary

Meetings longer than 60 minutes hit the OpenAI Realtime API session limit and the WebSocket dies silently. Audio keeps flowing to a dead socket, no reconnection happens, and the user loses all transcription from that point on. This PR adds automatic reconnection with a proactive timer at 55 minutes (graceful, zero audio loss) and a reactive fallback on session_expired (safety net with pre-connect buffering).

Separately, the ONNX worker was missing from production builds because src/workers/ wasn't in the electron-builder file list or asarUnpack config. The worker crashed in a loop on every app launch after any note was saved. This broke semantic search on all platforms.

Changes

• src/helpers/openaiRealtimeStreaming.js: proactive session timer at 55min, onSessionExpired callback, session_expired error interception, pre-connect audio buffer when ws is null
• src/helpers/ipcHandlers.js: reconnectMeetingStreams() function that swaps streaming instances before token fetch, fetches new credentials, connects, then disconnects old instances. Guard against concurrent reconnects and cap at 5 reconnects per session
• electron-builder.json: added src/workers/**/* to files and asarUnpack
• src/helpers/onnxWorkerClient.js: path fix from app.asar to app.asar.unpacked for utilityProcess.fork()
• test/helpers/openaiRealtimeStreaming.test.js: 17 tests covering session expiry handling, pre-connect buffer, cold-start flush, zero-audio-loss verification across reconnect boundary, concurrent expiry guard