feat(lens): allow microphone and speaker access

[JongSikLim]

Summary

• allow the active Lens page to play audio, capture microphone input, and select an audio output device while rejecting camera, unrelated, popup, and stale-view requests
• add the macOS microphone usage description and audio-input entitlements
• document the permission behavior and add focused policy and packaging tests

Verification

• bun test tests/lens-audio-permissions.test.ts tests/lens-browser-manager.test.ts tests/lens-url.test.ts tests/scripts-smoke.test.ts (39 passed)
• bun run typecheck
• bun run build:desktop
• bun run check:doc-paths
• bun run check:max-lines-ratchet
• bun run check:switch-exhaustiveness
• plutil -lint build/entitlements.mac.plist build/entitlements.mac.inherit.plist
• Electron 41 Lens runtime smoke: acquired one live microphone track, selected an output sink with setSinkId, and rejected camera capture with NotAllowedError

[heath-s]

Approved