feat(deps): add chat thinking support

[hubertshelley]

add ChatThinking request fields for chat completions and

add reasoning_content fields in chat response/message delta.

also make workspace rust-version explicit for path usage and

fix clippy let_underscore_future warnings in config tests.

[DenysVuika]

@64bit is there any change to get this PR going? thanks

[hubertshelley]

@64bit is there any change to get this PR going? thanks

@DenysVuika support think mode for DeepSeek and glm

[64bit]

Thanks for PR and bump. This one is recurring theme where I see contributions for non-openai types, and they are out of scope and are noted as such in contributions.md.

For this reason, the byot - bring your own types - feature exist. So you can write custom types and not having to merge it into the crate.