• Add tool support for OpenRouter by propagating tool support from the supported_parameters field in the models API output
• Remove unnecessary second fetch of structured_outputs.
• Update recorded HTTP API interactions and snapshots.
• Add tool support test.

This resolves:

• support tool calling #38
• adds tool support #39

Note that streaming tool calls to certain models may still fail in version of llm up to 0.26 [edit: fixed in llm 0.27] due to:

• Streaming tool calls with no arguments don't work with Qwen 3 llm#1191

Note:

This is an alternate, smaller PR equivalent to #42. Compared to #42, the cassette recordings now only include a subset of models supported by OpenRouter, instead of the entire 400k response.