Add immersive WebXR mode for Quest and other headsets

[kburzota]

Summary

• Enter VR / AR (passthrough) with a locomotion rig, controller → office key mapping, and controller rays for aiming.
• Worker terminals open on a floating panel you can point at and press keys on without taking the headset off.
• Settings gains a Faster / Outline control for VR rendering; the outline also drops itself below ~72 fps.

Test plan

• npm run typecheck
• npm test (606 pass)
• npm run build
• On a Quest (or WebXR emulator): Enter VR, walk with left stick, snap-turn with right stick, open a terminal with the trigger and use the panel keys
• Enter AR and toggle table / life-size with the right grip

Made with Cursor

[kburzota]

Opened against the wrong repo; moved to my fork.