[JEWEL-1137] Added FPS counter to the Jewel sample app

[faogustavo]

• Added a simple way to track the app frame rate to help identify any possible bottlenecks

No release notes as it's just in the sample app

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Note

Adds a composable FPS counter with selectable counting modes, toggleable from Welcome view, and displayed in the title bar.

• Samples UI:
  • New Component: components/FpsCounter.kt measures FPS (real-time, fixed interval, fixed frame count), tracks min/max, and color-codes output.
  • Title Bar: Conditionally displays FpsCounter in TitleBarView when MainViewModel.showFPSCount is true.
  • Welcome View: Adds "Show FPS Count" checkbox to toggle visibility.
  • ViewModel: Introduces showFPSCount state in MainViewModel.

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[cursor]

Bug: Time Collisions Cause FPS Instability

Division by zero: if two consecutive frames occur at the exact same millisecond timestamp, frameTimeMillis - lastUpdTime.getAndSet(frameTimeMillis) equals zero, causing division by zero and storing Infinity in fpsArray. This leads to incorrect FPS calculations and potentially NaN values when averaging.

 

[rock3r]

I would just... not add an FPS counter. The meaning of the value it shows is misleading at best, and I am worried people might get complacent that slow code is still not impacting the framerate of redraws (which is capped to the screen's framerate...), while not seeing that there might be several recompositions and wasted work for each of those frames.

[faogustavo]

Makes sense, I'll just close this PR. I just opened as it was part of the base branch for lazy table and it could be useful in some situations.