meta: Add dual-function-keys

dual-function-keys is an amazing piece of software that solves many if
not all of the long-lasting issues I had with binding caps lock to ctrl
and escape. I have additionally configured it in a way such that print
screen can double as a right super key, due to it being next to right
alt and right ctrl on the T14.

dual-function-keys/.config/dual-function-keys.yaml

@@ -0,0 +1,10 @@
+TIMING:
+    - TAP_MILLISEC: 1000
+    - DOUBLE_TAP_MILLISEC: 0
+MAPPINGS:
+    - KEY: KEY_CAPSLOCK
+      TAP: KEY_ESC
+      HOLD: KEY_LEFTCTRL
+    - KEY: KEY_SYSRQ
+      TAP: KEY_SYSRQ
+      HOLD: KEY_RIGHTMETA

dual-function-keys/README.md

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+# dual-function-keys
+
+[dual-function-keys][dual-function-keys] is a way to give your keys multiple functions.
+
+## Use Cases
+
+dual-function-keys can be used to:
+
+- Have a caps lock key that works as ctrl and escape, without having your real ctrl key function as another escape key
+- Have one keybinding config that works across Xorg, Wayland, and ttys
+- Replace xcape, xmodmap, setxkbmap, keystrings, and similar technologies
+
+You should not use dual-function-keys if:
+
+- You should use dual-function-keys.
+
+[dual-function-keys]: https://gitlab.com/interception/linux/plugins/dual-function-keys