Closes#408
Previously `_init_client` assigned the raw `ollama` module to
`self.client`, so the `base_url` parameter was silently ignored and
every request hit the default localhost:11434. Now an `ollama.Client`
instance is created with `host=self.base_url`, so remote Ollama servers
are reachable.
Three regression tests added to prevent recurrence:
- default base_url is forwarded as host
- custom base_url (e.g. http://192.168.1.3:11434) is forwarded as host
- self.client is never the raw module
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Verify that temperature parameter is omitted from API calls when None,
allowing models to use their defaults. Tests cover OpenAI, Groq, Gemini,
Ollama, and DeepSeek providers.
