Add outline toggle control to stress test example

[bhairaav]

Summary

Added an outline rendering toggle to the stress-500-walls.html example that allows users to enable/disable outline rendering on all 1500 elements (walls, doors, and windows) simultaneously. This includes:

• New applyOutline() function that toggles the outline property on all elements and measures performance
• New "Rendering" folder in the GUI with an "Outline (all elements)" checkbox control
• Performance tracking for outline toggle operations via the existing recordRoundtrip() utility

Verification

The changes are isolated to the example file and add a new interactive control. The implementation follows the existing patterns in the codebase (similar to applyViewMode() and other toggle functions). The performance measurement integrates with the existing roundtrip recording system.

Docs And Examples

Updated the stress test example to demonstrate outline rendering control as a performance measurement scenario.

Reviewer Notes

• The outline toggle operates on all 1500 elements and records the operation time, making it useful for performance profiling
• The implementation mirrors existing toggle patterns in the file for consistency
• No changes to core library code; this is purely an example enhancement

Checklist

• I ran the relevant validation for the areas I changed
• I updated docs and/or examples when user-facing behavior changed
• I did not hand-edit generated output such as dist/ or examples/dist/

https://claude.ai/code/session_01QVPvseDLHFA7x1b2kYJ1mP