Jalan KL original runtime integration

Source: the owner's jalan-kl project, copied 29 September 2026.
The original world construction, live terrain, roads, KLCC Park, planting,
landmarks, LRT, street food, residents, sky, cameras, culling,
asset streaming and adaptive graphics are preserved.
The F1 adapter replaces the walking avatar and input; the parent F1 page
provides the single two-axis logo driving wheel. The original source is
retained in vendor/jalan-kl/upstream; the build applies a small adapter.
Original Jalan KL project and Blender files remain unchanged.

Third-party notices: /jalan-kl/THIRD_PARTY_NOTICES.txt
Basemap data notices: /jalan-kl/maps/THIRD_PARTY_NOTICES.txt

F1-specific adaptation: civilian traffic and parked cars are replaced by
21 F1 racing rivals. Procedural instanced race barriers, kerbs, tyre stacks
and three starting-light gantries are built in vendor/jalan-kl/f1/race-world.js.