- Move parse_args to codai.cli
- Move main() to codai.main
- Simplify coderai to be a thin wrapper importing from codai package
- Create codai.api module with organized endpoints:
  - codai/api/app.py: FastAPI app, /v1/models, /v1/files, get_load_mode
  - codai/api/text.py: /v1/chat/completions, legacy /v1/completions
  - codai/api/images.py: /v1/images/generations
  - codai/api/transcriptions.py: /v1/audio/transcriptions
  - codai/api/tts.py: /v1/audio/speech
- coderai is now backward compatible entry point only