feat: Move iTerm to OSC9;4 supported terminals

[Maks3w]

On Nov 17th iTerm has released v3.6.6 with OSC 9;4 support

iTerm2 version 3.6.6 was released on
November 17, 2025.

New Features:
- Added setting to show per-pane title bars when
  there is only one pane.
- If the previous release left you with red tabs
  in a tmux window, this one will offer to fix
  them.
- Add KeePassXC integration in password manager.
- There's a new key binding action to toggle a
  checkbox of your choosing in settings.
- Add support for OSC 9;4 progress bars.
- Add support for DECDSR 997 and DECSET/DECRESET
  2031 for dark mode reporting.
- Cursor animation can now be enabled always.
  Previously it only happened in interactive apps.
https://iterm2.com/downloads.html

[Copilot]

Pull request overview

This PR updates iTerm2's classification in the OSC 9;4 terminal support detection logic following the release of iTerm2 v3.6.6 on November 17, 2025, which added support for OSC 9;4 progress bars.

Key changes:

• Moved iTerm2 from unsupported to supported terminals for OSC 9;4 sequences
• Updated documentation to reflect iTerm2's new capability

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/ui/osc.rs	Moved iTerm.app detection from unsupported to supported terminals list
settings.toml	Removed iTerm2 from the list of terminals that don't support OSC 9;4

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[Copilot]

The list of supported terminals should be alphabetically sorted for better maintainability. Consider reordering the entries so 'iTerm.app' comes before 'ghostty' or after 'vscode' depending on the sorting approach (case-sensitive or case-insensitive).

[risu729]

The failing CI should pass now, please update this branch.

[Maks3w]

done