Add Ollama Cloud (ollama.com) as a built-in provider with both model
hosting and web search/fetch capabilities.
Model provider:
- 13 curated models via OpenAI-compatible API (Llama 3.1, Qwen 3,
DeepSeek R1, Gemma 3, Mistral, Phi-4, GPT-OSS)
- Auth via OLLAMA_API_KEY environment variable
- Registered in onboarding, env hydration, and model resolver
Web tool provider:
- Search via POST ollama.com/api/web_search
- Page fetch via POST ollama.com/api/web_fetch (fallback after Jina)
- Added as third search provider option alongside Tavily and Brave
- /search-provider command updated with ollama option
Closes#430
ecf8125e39