(studio) Add keyboard shortcuts to toggle muting and looping (NLE standards) #905

Problem

Currently, toggling muting and looping in the player requires mouse interaction. For power users and fast previews, this slows down the workflow. Many non-linear editors (NLEs) use hotkeys for these actions, and the lack of shortcuts makes the experience less efficient for users accustomed to rapid playback control.hv

Proposed solution

Add keyboard shortcuts to control muting and looping during playback.

• M to toggle audio mute/unmute
• Ctrl+L or Shift+L to toggle looping (matching common NLEs, e.g., DaVinci Resolve, Premiere, Final Cut)