New StickyIndicator

[bdlukaa]

Update StickyNavigationIndicator to match the new Win 11 Design.

Fixes #173
Fixes #178

• Renamed _NavigationBody to InheritedNavigationView
• Removed NavigationIndicatorState.sizes. Size, if necessary, can be fetched using LayoutBuilder. offsets is untouched
• Indicators are now handled inside of PaneItem instead of NavigationPane
• Indicators are no longer created using a function
• Added equality operators to NavigationPane

In general, the performance improvement is for both sticker and end indicators, since they no longer depends on global coordiantes to render. This also fixes the issue that the indicator was still shown even if the item was hidden by the pane scroll view.

I know this comes with limitations, but the gains are better than the losses.

Pre-launch Checklist

• I have updated CHANGELOG.md with my changes
• I have run "optimize/organize imports" on all changed files
• I have added/updated relevant documentation

[klondikedragon]

I can confirm with these changes the CPU performance issue is solved for me! Before these changes, even when app was idle but with the navbar displayed, it was in a constant build/render loop... using Chrome devtools to profile webpage performance on web platform, it was using up about 40% of one CPU core:

After building using these changes, the CPU usage is 0% and chrome profiling shows no build/render calls with the page idle. I only tested on the web platform, but the results should translate over into other platforms as well...