Investigate/Fix CPU utilization

[MatthiasGrandl]

Loungy is pretty heavy on CPU. It's not acceptable for it to use 1.5% of my CPU while running in the background, draining my battery.

Even worse, it seems after some sleep/wakeup cycles Loungy sometimes goes into a state of hogging the entire CPU, making my MacBook run hot and draining the battery insanely fast. I have yet to figure out what causes this.

[MatthiasGrandl]

I fixed the wakeup issue in GPUI, waiting for feedback from upstream if the fix can be upstreamed, but for Loungy purposes it works nicely.

[MatthiasGrandl]

Another issue is the current clipboard implementation. If you have a big image in the clipboard, it's bytes get hashed every second, which causes huge CPU utilization. Instead of polling arboard I should implement a platform specific clipboard watcher that notifies the clipboard module somehow.

done