Keyboard patch cleanup; arrow icons centered again

- drop cruft: v4 DispatchKeypress undo, unused VKM import and
  __vrkbdPatched flag, redundant VRKBD_DISPLAY env in the unit
- one wrap() helper for all replaced functions; key names for the
  stylesheet derived from the key definitions instead of repeated
- unpatch: restore every layout ever patched (also ones disabled since)
  and the remembered component class instead of walking the tree again
- helper: debounce re-injects after bursts of new JS contexts; resolve
  pending DevTools calls when the connection closes
- arrow icons vertically centered again (hint stays at the bottom edge)
- updated header comments

modules/steam-keyboard-patch/unpatch.js

@@ -2,28 +2,23 @@
 // when it stops (service stopped, module disabled). Every patched function
 // keeps its original as __vrkbdOrig. Safe to run when nothing is patched.
 (() => {
-  const wr = window.__vrkbdWr;
-  if (!wr) return 'not patched';
+  if (!window.__vrkbdWr) return 'not patched';
   const unwrap = (obj, name) => {
     const f = obj?.[name];
-    if (f && f.__vrkbdOrig) obj[name] = f.__vrkbdOrig;
+    if (f?.__vrkbdOrig) obj[name] = f.__vrkbdOrig;
   };
-  const Layouts = wr(40222);
-  for (const l of [...(Layouts.G$() || []), Layouts.r_()]) unwrap(l, 'rgLayout');
+  for (const l of window.__vrkbdLayouts || []) unwrap(l, 'rgLayout');
   unwrap(SteamClient.Input, 'ControllerKeyboardSendText');
-  unwrap(wr(5363).PE.prototype, 'DispatchKeypress');
-
+  unwrap(window.__vrkbdProto, 'TypeKeyInternal');
   clearInterval(window.__vrkbdHoldTimer);
+
   const inst = window.__vrkbdInst;
   if (inst) {
-    let proto = Object.getPrototypeOf(inst);
-    while (proto && !Object.prototype.hasOwnProperty.call(proto, 'TypeKeyInternal')) proto = Object.getPrototypeOf(proto);
-    unwrap(proto, 'TypeKeyInternal');
     delete inst.__vrkbd;
-    inst.setState({ standardLayout: Layouts.r_() });
+    inst.setState({ standardLayout: window.__vrkbdWr(40222).r_() });
     inst.forceUpdate();
   }
   for (const p of g_PopupManager.GetPopups?.() || []) p.window?.document.getElementById('vrkbd-style')?.remove();
-  for (const k of ['__vrkbdHoldTimer', '__vrkbdHeld', '__vrkbdInst', '__vrkbdPatched']) delete window[k];
+  for (const k of ['__vrkbdHoldTimer', '__vrkbdHeld', '__vrkbdInst', '__vrkbdProto', '__vrkbdLayouts']) delete window[k];
   return 'unpatched';
 })()