feat: add macos microphone input selector

[zly2006]

Summary

• Add a persisted microphone selection setting with System Default fallback.
• List available input devices via CPAL and expose them through a Tauri command.
• Use the selected input device when starting capture, with startup validation for missing devices.
• Add localized settings labels for the microphone selector.

Validation

• cargo check
• npm run format:check
• NODE_OPTIONS='--localstorage-file=/tmp/opentypeless-vitest-localstorage' npm test
• npm run build

Notes

• Device IDs currently use CPAL device names because CPAL does not expose stable cross-platform input device IDs.

[tover0314-w]

Review update: this should be rebuilt before merge.

The feature is valid, but the PR is currently conflicting and should not be resolved by a broad direct merge. The safer path is a focused microphone-input-selector PR that preserves existing recording behavior and has explicit fallback behavior when a saved device disappears.

Expected before landing:

• resolve conflicts against current main
• persist selected input device safely
• fall back clearly if the device is missing/unavailable
• verify macOS recording still works with default input and selected input
• add focused config/storage tests where possible

This was not merged into the local issue-remediation branch I just validated.