This PR keeps the Browser Agent runtime behavior as-is and only adds in the model-preset option for browser runs (highly requested by our users).
The Browser Agent can now use either:
- the effective Main Model from `_model_config`, or
- one saved `_model_config` preset dedicated to browser tasks
- this PR brings back LLM customization for Browser Agent plugin, but without over engineering. Model presets-only, not custom provider + LLM, like we have in Email Integration.
- created a separate `browser-agent-store.js` page store to remove JS from within x-data in the HTML markup of main.html
