Drive with a leader arm: plug it into a computer (or Android phone) and the browser streams its pose as your commands during your turn #18

Goal (owner, 2026-10-20): complete, secure, public control of the real arm from the public forge URL, with a moderated community. Simple and amazing to use; every knob the owner might want is an admin setting.

Milestone 3. In the browser, Web Serial (Chrome/Edge desktop; Android Chrome where Web Serial/WebUSB is available) reads the Feetech leader arm (same protocol as Software/so101's FeetechBus) and sends joint targets over the existing WebSocket - only while it is your turn, through the same server-side safety limits. A "Connect leader arm" button, a live mirror of the leader pose before you take control, and a clear message on browsers that cannot (iOS Safari: explain, offer keyboard/touch). Tests: a fake serial port drives the simulated arm; commands outside your turn are dropped; limits still clamp.