[mvanhorn]

Adds gemini-3-pro to the Google provider model list per #405.

Changes:

• api/config/generator.json - new gemini-3-pro entry in providers.google.models with the same temperature/top_p/top_k shape as the existing 2.5 entries
• api/api.py:217-221 - mirror the addition in the exception-path fallback ModelConfig so 3 Pro still surfaces in the dropdown if load_generator_config() raises

default_model for the Google provider stays at gemini-2.5-flash, so existing users see no behavior change. Users opt into 3 Pro explicitly via the model picker.

Pattern matches PR #420 (Bedrock model additions) and the original 2.5 family additions in PR #318.

Fixes #405

[gemini-code-assist]

Code Review

This pull request adds support for the Gemini 3 Pro model by updating the model list in the API and providing its configuration in generator.json. Feedback was provided to reorder the models in the API fallback list to ensure consistency with the configuration file and prevent potential issues with default model selection in the frontend.

[jiaxi-xu-fsx]

Small follow-up: I think gemini-3-pro is already superseded by gemini-3.1-pro-preview in the latest Gemini API docs. We should probably switch to gemini-3.1-pro-preview (or include both for compatibility).

Reference: https://ai.google.dev/gemini-api/docs/models/gemini-3.1-pro-preview

[mvanhorn]

Good catch, thanks! Pushed f9532d8 adding gemini-3.1-pro-preview to the google provider model list alongside gemini-3-pro. Kept both so users on the older alias keep working while anyone wanting the newer preview can opt in.

Left gemini-3-pro (not gemini-3.1-pro-preview) in the api.py error-fallback path since that's the "configs failed to load" branch and a stable model is the safer default there.

[mvanhorn]

Merged main and slimmed this down (head 43edc72).

• Main split api/api.py into routers, and its error fallback in api/routers/system.py now lists only gemini-2.5-flash. I left that as is, so the fallback-order review note no longer applies.
• @jiaxi-xu-fsx was right that the 3 Pro entry should go. gemini-3-pro was never a Gemini API model id (the preview was gemini-3-pro-preview), and Google's models page now lists gemini-3-pro-preview as shut down. I removed it.

The PR now just adds gemini-3.1-pro-preview to the Google models in api/config/generator.json.