Fix macOS mouselook freeze on window switch + hot-path optimizations

[deliro]

Fix — macOS stuck cursor after switching windows

A MouselookStop() issued while the window is backgrounded (e.g. bags/LFG auto-unlock Mouse Look during an alt-tab) leaves the OS mouse capture stuck: on return the cursor/camera are frozen while IsMouselooking() no longer reflects reality. There is no focus event to hook.

• Auto-recovery (CM.ResyncMouselookOnFocusRegain): when frames halt while backgrounded (fullscreen), the gap between OnUpdate frames signals the regain → force a clean mouselook re-grab.
• Manual recovery (Combat Mode - Reset Mouse Look keybind): when the window keeps rendering while backgrounded (windowed background FPS), the freeze can't be detected from OnUpdate, so a keybind re-grabs + releases capture on demand.

Optimizations (throttled OnUpdate hot path)

• Custom condition: cache the loadstring compile instead of recompiling every tick — the default empty string was being compiled ~7×/sec for every user.
• IsUnlockFrameVisible: check GetUIPanel first to short-circuit the ~170-frame visibility scan in the common case; ipairs instead of pairs.

🤖 Generated with Claude Code

[sampconrad]

Thanks for the work on this, @deliro! I had no idea about the macOS issue.

I'm not currently subscribed to the game, so I can't really test the proposed changes. The next time Blizzard breaks something that requires me to update the addon, I'll merge this and include it in the next release.