Standardize service lifecycle management by replacing `stop` with `exit` and introducing `is_exited` check

Refactor speech recognizer, audio capture, and system routes for improved clarity and functionality

Add pause and resume functionality to voice dialogue system

Refactor imports in `whisper.py` and `funasr.py` to use absolute paths for `ensure_minimum_audio_duration`.

Update `moyoyo.py`: add fallback for `utils` to ensure `HParams` availability in runtime.

Refactor imports for consistency in `kokoro.py` and `processor.py`. Use absolute paths for better readability and maintainability.

Rename 'src/VoiceDialogue' to 'src/voice_dialogue'.