Implement per-controller ABXY toggle

controller_hotkey_config.h

@@ -0,0 +1,17 @@
+// Compile-time AIO controller hotkey configuration.
+
+#pragma once
+
+// Bluepad32 button masks. Default chord: L + R + SELECT + START.
+#define SWITCH_ABXY_HOTKEY_BUTTON_MASK \
+    (BUTTON_SHOULDER_L | BUTTON_SHOULDER_R)
+#define SWITCH_ABXY_HOTKEY_MISC_MASK \
+    (MISC_BUTTON_SELECT | MISC_BUTTON_START)
+
+// 0 starts each new connection in Nintendo positional layout; 1 starts swapped.
+#define SWITCH_ABXY_DEFAULT_SWAPPED 0
+
+// Local confirmation pulse sent only to the controller that toggled.
+#define SWITCH_ABXY_FEEDBACK_DURATION_MS 120
+#define SWITCH_ABXY_FEEDBACK_WEAK_MAGNITUDE 0x80
+#define SWITCH_ABXY_FEEDBACK_STRONG_MAGNITUDE 0x80