Inject Remote lock keys instead of retiring keyboard input

Refusing Caps, Num and Scroll Lock retired all remote input, so a
controller using Caps Lock as its screen-reader modifier lost keyboard
control on the first press. Lock keys are now owned like other keys and
released once at retirement without another toggle.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/testing/remote-key-target.md

@@ -62,7 +62,7 @@ fixture changes maps and lock state explicitly to exercise these cases.
 See the [XKB library specification](https://xorg.freedesktop.org/archive/current/doc/libX11/XKB/xkblib.html)
 for `XkbGetMap`, `XkbGetState` and `XkbTranslateKeyCode`.
 
-Lock-key downs are unavailable until lock synchronization and reader modifier
+(Superseded: see Lock keys below.) Lock-key downs were unavailable until lock synchronization and reader modifier
 handling have a defined policy. This includes Caps Lock even when a reader
 configuration would otherwise use it as a modifier. AltGr, IME/dead keys,
 general group/level handling and exact remote autorepeat remain unfinished.
@@ -114,3 +114,15 @@ external Remote race suite, affected-package vet, a separate reader build,
 the existing speech regression harness and Tentacles `make check` passed.
 No full reader suite, installed-binary behavior,
 audible speech, physical input/Braille or live NVDA/Orca acceptance was performed.
+
+## Lock keys (2026-11-06)
+
+Caps Lock, Num Lock and Scroll Lock are now owned like other keys instead of
+being refused. Refusal retired all remote input, so a controller using Caps
+Lock as its NVDA or Cthulhu modifier lost keyboard control on the first press.
+A remote press and release toggles the lock here, as the same physical key
+would. Retirement releases a held lock key once and never re-toggles a lock;
+when Caps Lock is the controlled reader's Cthulhu modifier, the command owner
+keeps its local lock state. A private Xvfb test checks that each lock key is
+owned and released at retirement. Lock-state synchronization between computers
+is not attempted.