Add setting for font sizes in Roo

[Vega-KH]

What specific problem does this solve?

The text in Roo is small and can be difficult to read on high dpi displays, or small monitors. It uses a smaller font size than the code editing windows, so I only want to increase the size of the Roo Code text and not zoom the entire vscode window.

Editing the Roo css file directly is the only solution currently, but that is tedious as it is located in user settings, and is minified. I propose that we add a setting, so users can choose between small, medium, and large text.

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Roo Code Task Links (Optional)

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Request checklist

• I've searched existing Issues and Discussions for duplicates
• This describes a specific problem with clear impact and context

Interested in implementing this?

• Yes, I'd like to help implement this feature

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