VR keyboard: cleanup of the controller bridge, gesture input and docs

- gesture-input.js: drop the unused mode getter and release().
- relay.mjs: both sides have a binding; no condition.
- hub.js: the frame cadence is documented once (bridge-patch.js); errors
  listed.
- docs: the bridge's idle cost and "one word at a time" stated once;
  twoHanded's README row points to the docs; rewrapped lines.

modules/vr-keyboard-controllers/hub.js

@@ -3,17 +3,16 @@
 // extraArgs (like lib/hooks.js): installs window.__sfuiControllers unless an
 // equal or newer VERSION is there (a newer one takes over the subscribers)
 // and evaluates to it. relay.mjs calls frame(f) with bridge-patch.js's
-// frames and lost() when the SteamVR side goes away.
+// frames (cadence there) and lost() when the SteamVR side goes away.
 //   subscribe(fn) -> unsubscribe   fn(frame) per frame, fn(null) when lost
 //   last                           the last frame (null: none / lost)
 //   demand(ms)                     full rate for the next ms (0: end), e.g.
 //                                  during a laser press; via the relay's
 //                                  CDP binding __sfuiCtlIn
+//   errors                         { count, last } of throwing subscribers
 // Each frame's hand points (tip, ray) get the keyboard page's px: x, y
 // (CSS px of the keyboard popup) and onKeyboard (inside the page), if the
-// keyboard popup exists. Frames come at up to ~90 Hz while a hand's tip is
-// within 10 cm of the keyboard or its trigger is pulled, else every 1 s, and
-// only while SteamVR shows the keyboard (then one with keyboard null).
+// keyboard popup exists.
 (() => {
   const VERSION = 2;
   const G = globalThis;

modules/vr-keyboard-controllers/relay.mjs

@@ -56,7 +56,7 @@ async function connect(side) {
   const closed = new Promise((res) => { ws.onclose = res; });
   // No Runtime.enable: bindings work without it, and it would stream the
   // page's console and context events here.
-  if (cfg.binding) send('Runtime.addBinding', { name: cfg.binding });
+  send('Runtime.addBinding', { name: cfg.binding });
   live[side] = (expression) => send('Runtime.evaluate', { expression });
   console.log(`${side}: connected`);
   await closed;

modules/vr-keyboard/gesture-input.js

@@ -30,7 +30,7 @@
 // attribution. No fresh frames at the press: touch events only, as without
 // the bridge.
 (() => {
-  const VERSION = 2;
+  const VERSION = 3;
   const STALE = 150, GAP = 60, TOL = 30, AGREE = 40, FAR = 60, WAIT = 250, LATE = 60;
 
   function create({ now = () => performance.now() } = {}) {
@@ -89,7 +89,6 @@
       VERSION,
       get owner() { return owner; },
       get hand() { return hand; },
-      get mode() { return mode; },
       stats,
       // { phase, id, x, y, target } if the event concerns the gesture (or may
       // start one: phase 'down'), else null. An 'up' or 'cancel' ends the
@@ -148,7 +147,6 @@
         if (!hand) { waitUntil = touchAt + WAIT; refs = [[c.x, c.y]]; }
         return hand;
       },
-      release() { reset(); },
       // A bridge frame (null: bridge lost). Returns [x, y] to add to the path, or null.
       frame(f) {
         const t = now();

modules/vr-keyboard/patch.js

@@ -10,9 +10,10 @@
 //   started on at release. With both lasers on the keyboard the pressing one
 //   may get no touchmoves; its path then comes from the controller bridge
 //   (gesture-input.js: the hand whose laser hit the press point; full rate
-//   asked for from the press to the release). Once a press leaves its first key we drop that
-//   key from Steam's pending touches (m_mapTouched) and cancel its long press
-//   (Steam's own touch-end cleanup, minus the typing), then decode the path.
+//   asked for from the press to the release). Once a press leaves its first
+//   key we drop that key from Steam's pending touches (m_mapTouched) and
+//   cancel its long press (Steam's own touch-end cleanup, minus the typing),
+//   then decode the path.
 // - Output: one character or "Backspace" per HandleVirtualKeyDown, the path
 //   of Steam's own keys (incl. extraKeys' xdotool fallback for non-ASCII,
 //   which is async: we pause after such characters).