Add Settings Page for Theme Selection and UI Preferences in the IDE

[navneetprajapati26]

Issue Description

Feature Request:
I would like to introduce a new Settings page in the IDE that allows users to manage basic customization preferences. This will improve user experience and provide more control over the app appearance.

Proposed Features

• Theme selection (Light / Dark / System default)
• Font size and UI scale adjustment (optional if maintainers agree)
• Save user preferences locally (e.g., using shared_preferences or similar storage)
• Accessible through a dedicated “Settings” option in the sidebar or app menu

Why This Is Needed

Currently, the IDE does not provide an option for users to change the look and feel of the interface. Adding a settings page will:

• Enhance personalization and usability
• Improve accessibility for users with visual preferences
• Provide a foundation for adding more configuration options in future

Possible Implementation Approach

• Create a new route/screen named SettingsPage
• Use a state management solution already used in the project, or provider if not integrated yet
• Store preferences persistently using shared_preferences or another preferred method
• Apply theme changes using ThemeMode in MaterialApp

Additional Notes

I am happy to work on this feature and submit a PR once the idea is approved.
Please share feedback or any guidelines I should follow before implementation.

[ankurg132]

Go for it @navneetprajapati26