Fix audio capture stability and hotkey session handling

[Mctashuo]

Summary

• Replace the AVAudioEngine input tap with AudioQueue-based capture to avoid -10877 / CoreAudio startup failures and hangs after device route changes.
• Defer config reloads while a recording session is active, and debounce modifier-only hotkey releases to avoid accidental session interruption.
• Improve ASR close/error reporting by preserving provider close reasons, surfacing localized error summaries, and logging DoubaoIME handshake/session failures with more context.
• Fix setup window dark-mode colors.
• Add focused Objective-C logic tests for config reload deferral and hotkey release behavior.
• Add a lite Xcode project configuration and improve Makefile install/build helpers.

Tests

• git diff --check missuo/main...HEAD
• cargo test -p koe-core -p koe-asr