feat: add all OCI GenAI models — 26 chat models and 9 embedding models
Complete model catalog from Oracle Cloud Infrastructure GenAI docs:
- Cohere: Command A Reasoning, Vision, A, R+, R
- Meta: Llama 4 Maverick/Scout, 3.3 70B, 3.2 90B/11B Vision, 3.1 405B
- Google: Gemini 2.5 Pro, Flash, Flash-Lite
- xAI: Grok Code Fast 1, 4.1 Fast, 4 Fast, 4, 3, 3 Mini, 3 Fast, 3 Mini Fast
- OpenAI: GPT-oss 120B, 20B
- Embeddings: Cohere Embed v4.0, English/Multilingual v3.0 + Light + Image variants
- Updated model IDs to match official OCI SDK format
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