Specify the LLM model for generating git commit messages

[b1d-farewell]

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What are you proposing?

I hope to add a model selection feature to the git commit message editor toolbar, allowing users to choose other potentially more suitable models beyond the current default strategy of matching the agent's model

Why does this matter?

Some models may be faster, cheaper, or more accurate in understanding diffs, among other advantages. In short, having more options never hurts.