fix: filter tools in Ollama streaming when chat mode is enabled

[blackgirlbytes]

Summary

Fixes #6117

When using chat mode with Ollama models that don't support tool calling (e.g., deepseek-coder:6.7b), users were getting a 400 error:

Request failed: Bad request (400): registry.ollama.ai/library/deepseek-coder:6.7b does not support tools.

Root Cause

The stream() function in the Ollama provider was not checking GooseMode::Chat and always passed tools to the API. The complete_with_model() function already had this check, but since streaming is the default behavior, the bug affected most users.

Changes

Added the same GooseMode::Chat filtering logic to the stream() function that already exists in complete_with_model():

let config = crate::config::Config::global();
let goose_mode = config.get_goose_mode().unwrap_or(GooseMode::Auto);
let filtered_tools = if goose_mode == GooseMode::Chat {
    &[]
} else {
    tools
};

Testing

• Verified the fix compiles successfully
• Verified clippy passes with no warnings
• Manual testing with deepseek-coder:6.7b in chat mode should now work without errors

Did I use AI?

Yes, I did. While I was looking into the problem, goose wanted to fix it, and the fix seemed plausible.

[Copilot]

Pull request overview

This PR fixes a bug where Ollama models without tool calling support (e.g., deepseek-coder:6.7b) were receiving 400 errors in chat mode. The fix applies the existing tool filtering logic from complete_with_model() to the stream() method, ensuring both code paths respect GooseMode::Chat.

• Adds GooseMode::Chat filtering to the stream() function
• Mirrors the existing pattern in complete_with_model() for consistency

[michaelneale]

fantastic catch @blackgirlbytes - I bet that has been hiding in there for ages