chore: bump bb-app + @bb/desktop to 0.0.9

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

chore: bump bb-app + @bb/desktop to 0.0.8

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

chore: bump bb-app + @bb/desktop to 0.0.9

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

desktop: rename version-feed script to .mts

Rename the desktop version feed generator to .mts so top-level await runs under the intended ESM loader.
Update the desktop package script to invoke the renamed file.
Source: bb/urgent-p0-fix-generate-version-feed-mts-thr_4uk45ncxfy (thr_4uk45ncxfy).

desktop: wire electron-updater auto-update

Add electron-updater integration behind the desktop update provider and preload IPC surfaces.
Extend the renderer update toast to report desktop update states and actions.
Keep automatic activation deferred to signed builds, with config, docs, and service tests in place.
Source: bb/wire-up-electron-updater-auto-update-for-bb-desk-thr_dh5v7xu2dq (thr_dh5v7xu2dq).