### Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [ ] Unsafe blocks (if any) have justifying comments ← N/A, no unsafe
blocks
- [x] The content is consistent with the UI/UX checklist
- [ ] Tests cover the new/changed behavior ← no existing tests; none
added
- [x] Performance impact has been considered and is acceptable

#### Closes #52881

### Fix

Add a `diagnostics_manually_toggled: bool` field to `Editor`. It is set
to `true` when the user toggles diagnostics off, and back to `false`
when they toggle them on again. `settings_changed` now skips the
severity override while this flag is set, preserving the user's intent
across settings reloads.


Video 

[Screencast from 2026-04-01
20-42-16.webm](https://github.com/user-attachments/assets/0e52868c-85bb-4270-b487-30bf50da97c2)


Release Notes:

- Fixed "Diagnostics" in Editor Controls re-enabling itself after being
manually disabled