Allow toggling Caps Lock via both Shift keys

Adds shift:both_capslock alongside compose:caps so pressing both Shift
keys together toggles real Caps Lock. Caps Lock alone remains the
Compose key, and single-Shift behavior is unchanged. Provides an escape
hatch when Caps Lock gets stuck on (e.g. after an fcitx5 desync).

Closes #5981

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

default/hypr/input.lua

@@ -28,7 +28,7 @@ hl.config({
     kb_layout = vconsole.XKBLAYOUT or "us",
     kb_variant = vconsole.XKBVARIANT or "",
     kb_model = "",
-    kb_options = "compose:caps",
+    kb_options = "compose:caps,shift:both_capslock",
     kb_rules = "",
     follow_mouse = 1,
     sensitivity = 0,