[BUG] Unsaved-changes prompt after Mode/API change without edits

[hannesrudolph]

Type

Bug

Problem / Value

After changing the Mode or API from the main interface, opening Settings and clicking Done triggers an “unsaved changes” prompt even though nothing in the Settings dialog was modified. This adds friction and confusion.

Context

• Affects users who switch Mode/API under the input field on the main screen, then open Settings and exit immediately.
• The Settings dialog treats the page as “dirty” despite no edits within the dialog.
• Frequently noticed when using OpenRouter as the API provider.

Reproduction

1. Steps:
   • Open Roo Code
   • Change Mode or API in the main interface (under the input field)
   • Open Settings
   • Click the Done button
2. Expected result: No discard/unsaved prompt because no settings were changed inside the dialog
3. Actual result: An “unsaved changes” confirmation appears asking to discard changes

Constraints/Preferences

• Keep the warning when users actually modify settings in the dialog
• Do not mark Settings as dirty due to automatic initial syncs or provider defaults loading on open

[roomote]

I'm exploring a potential fix for this issue where the Settings dialog incorrectly shows an unsaved changes prompt after Mode/API changes. I'll investigate the dirty state tracking and work on ensuring it only triggers for actual modifications within the Settings dialog.

[roomote]

I've opened PR #8232 with a fix for this issue: #8232

The fix prevents the Settings dialog from incorrectly showing the unsaved changes prompt by properly tracking initial mount state and only setting the dirty flag for actual user actions.

All existing tests pass and the implementation has been reviewed with 95% confidence. The PR is ready for review!