[BUG] Non-functional Eye Button on Timeline Track

Platform

Windows 11

Browser

Chrome 137

Current Behavior

The eye icon button on timeline track labels (left sidebar) is currently non-functional. It is displayed but does not respond to clicks, making it impossible to toggle track visibility.
Eye icon is visible on track labels
Clicking the icon triggers no action
No visual feedback (hover/active states)
Track content remains visible regardless of interaction

Expected Behavior

Clicking the eye icon should toggle track visibility
Visible State: Icon is a gray Eye
Hidden State: Icon becomes a red EyeOff

and track content becomes semi-transparent
Hidden tracks should not be included in the final export (if applicable)

Recurrence Probability

Always

Steps To Reproduce

1. Open a project in the editor
2. Add any media (video/image/text) to the timeline
3. Locate the track label on the left sidebar
4. Click the eye icon
5. Observe that nothing happens

Anything else?

This PR implements the missing functionality for the timeline track visibility toggle. It allows users to hide/show specific tracks, which is essential for complex editing workflows

Start at the timeline track labels in the editor's left sidebar and reproduce the click from the issue's steps. Trace the eye button's state and track rendering, then verify that visible tracks show Eye, hidden tracks show EyeOff with semi-transparent content, and hidden tracks are excluded from export when applicable.