Implement local compatibility APIs

[CobraSoftware]

overview

This is desgined to add more API endpoints for boarder compatiblity.
It was heavily assisted by AI.

Summary

This PR expands the local compatibility surface for the MLX-backed server while keeping inference local-only.

Main additions:

• OpenAI compatibility improvements, including broader response/resource coverage and realtime session support
• Anthropic and Ollama compatibility validation
• LM Studio native API support under /lmstudio/v1/*
• Deepgram-compatible local APIs under /deepgram/vl/*
• Model-family detection for Qwen3 Omni and Voxtral realtime variants
• Additional local implementations for practical OpenAI-style resource APIs such as files and persisted responses retrieval

What Changed

• Added LM Studio endpoints:

  • /lmstudio/v1/models
  • /lmstudio/v1/models/load
  • /lmstudio/v1/models/unload
  • /lmstudio/v1/models/download
  • /lmstudio/v1/models/download/status
  • /lmstudio/v1/chat

• Added Deepgram endpoints:

  • /deepgram/vl/listen
  • /deepgram/vl/speak
  • /deepgram/vl/read
  • /deepgram/vl/models
  • /deepgram/vl/models/{model_id}

• Expanded OpenAI-compatible surface:

  • Realtime session endpoints
  • Realtime client secrets
  • Realtime transcription sessions
  • Local files API
  • Local responses/{id} retrieval, delete, and input item listing
  • Broader spec alias coverage
  • Local-only 501 not_implemented_local fallback responses for remaining unsupported cloud paths

• Improved auth compatibility:

  • Authorization: Bearer <key>
  • Authorization: Token <key>
  • x-api-key
  • api-key

Testing

I tested compelation python3 -m py_compile vmlx_engine/server.py tests/test_deepgram_api.py tests/test_lmstudio_api.py tests/test_openai_spec_surface.py tests/test_realtime_compat.pyand did get all tests to passs but I lack the hardware to do larger in-depth realworld testing with bigger models.