Performance and UX improvements

[sudara]

This PR focuses on quality of UX and performance improvements.

• Resolves Consider restoring original overlay hover behavior #50
• Resolves Add FPS meter #62
• Resolves Color Picker Mouse Listener should be disabled unless color picker on  #65
• Resolves Color Picker's internal snapshot should only snap what's needed #66
• Resolves Color picker cursor glitches when target app/plugin changes cursor #67
• Resolves Item can appear selected in tree without actually being selected #68
• Resolves Initial click to toggle open inspector shouldn't select component in target app/plugin #70
• Resolves Hit ESC to clear tree selection #71
• Speedometer icon for FPS
• Improve support for switching between precompiled + cmake assets #58
• Integrate with melatonin_perfetto #75
• Display number of components in search placeholder text #77

TODO:

• Address Preliminary Perfetto findings #76
• Explore more perf improvements for "Chunky" feel (fps drop) when inspector first enabled on Windows #63
• Transparency grid bounds seems too wide #73
• Clicking to select propagates to app, which can be awkward #74

[sudara]

Merging for now and will followup on remaining todos.