Publish performance benchmarks

[artembobkin]

Establish and publish performance benchmarks so the engine's performance is transparent and regressions are easy to spot.

What to measure

• Frame time / FPS during pan, zoom, rotate, and globe/flat transitions
• Tile load time (network + parse + tessellation, up to first draw)
• Memory footprint (idle and under load)
• Live marker / avatar update cost with many markers on screen

Across devices

Run the same scenarios on a range of hardware and record the numbers, for example:

• A few iPhone generations (older and newer)
• iPad
• Apple silicon Mac

Compared to alternatives

Where it makes sense, put the numbers next to comparable renderers (MapKit, MapLibre / Mapbox) on the same device and scenario, so the trade-offs are honest and clear.

Output

• A short, reproducible benchmark setup others can run
• Results published in the repo (a doc or a page) and linked from the README

This is fairly self-contained and doesn't require deep engine internals, so it's a good first contribution.