Critical fixes:
- ALWAYS sync active AG X provider to endpoints.json on startup
(previously only synced on first run, causing LS to use stale data)
- Add --no-sandbox to proxy process spawns (fixes SIGTRAP crash on Linux)
- Add --no-sandbox for all Electron modes (not just headless)
- Add --ag-reset flag to re-trigger welcome screen
- Bump version to 2.0.4
Root causes fixed:
1. endpoints.json was never updated after first-run, so LS used wrong provider
2. Electron child processes (translation proxy) crashed due to SUID sandbox
3. No way to re-show provider selection after initial setup
b3c7be44e6