refactor: improve scene name and icon handling

[coderabbitai]

Objective

Refactor the way scene tree handles UI handles to properly separate icons from scene names instead of using string splitting.

Acceptance Criteria

• 1. Create a dedicated structure to store scene names and their associated icons separately
• 2. Update the scene tree to use this structure when displaying scene names
• 3. Remove the current string splitting approach in EditorScene.update()
• 4. Ensure backward compatibility with existing scenes
• 5. Add tests to verify correct handling of scene names with spaces

Dependencies

• PR refactor(inspector): refactor entity properties + window registry + docking registry #148 where this issue was identified

Technical Details

Environment: Editor
Components: Scene Tree, EditorScene
Resources: None

Background

This issue was identified in PR #148 (#148 (comment)) where we currently use string splitting to separate icons from scene names. This approach has limitations when scene names contain spaces.

Current problematic code:

m_windowName = utils::removeIconPrefix(selector.getUiHandle(m_sceneUuid, m_windowName));

The issue is that if a scene is named "my windows", the current approach would remove "my" from the name.

[iMeaNz]

This issue is no longer up to date