feat(hyprland): add directional focus binds

configs/nixos/modules/desktop/session/hyprland/default.nix

@@ -8,18 +8,56 @@
   options.modules.desktop.session.hyprland.enable = lib.mkEnableOption "the Hyprland compositor";
 
   config = lib.mkIf config.modules.desktop.session.hyprland.enable {
-    registry.keybind.${config.networking.hostName} = lib.listToAttrs (
-      map (workspace: {
-        name = "hyprland-workspace-${toString workspace}";
-        value = {
-          keys = "SUPER + ${toString workspace}";
-          action = {
-            kind = "focus-workspace";
-            inherit workspace;
+    registry.keybind.${config.networking.hostName} = lib.mkMerge [
+      # Generate numeric workspace keybinds.
+      (lib.listToAttrs (
+        map (workspace: {
+          name = "hyprland-workspace-${toString workspace}";
+          value = {
+            keys = "SUPER + ${toString workspace}";
+            action = {
+              kind = "focus";
+              inherit workspace;
+            };
           };
-        };
-      }) (lib.range 1 9)
-    );
+        }) (lib.range 1 9)
+      ))
+      # Generate directional keybinds.
+      (lib.listToAttrs (
+        map
+          (
+            { direction, key }:
+            {
+              name = "hyprland-focus-${direction}";
+              value = {
+                keys = "SUPER + ${key}";
+                action = {
+                  kind = "focus";
+                  inherit direction;
+                };
+              };
+            }
+          )
+          [
+            {
+              key = "H";
+              direction = "left";
+            }
+            {
+              key = "J";
+              direction = "down";
+            }
+            {
+              key = "K";
+              direction = "up";
+            }
+            {
+              key = "L";
+              direction = "right";
+            }
+          ]
+      ))
+    ];
 
     # This program integration owns the session, portals, and polkit, launched
     # through the universal Wayland session manager.
@@ -53,8 +91,8 @@
             (lib.generators.mkLuaInline (
               {
                 exec = "hl.dsp.exec_cmd(${lib.generators.toLua { } keybind.action.command})";
-                "focus-workspace" = "hl.dsp.focus(${
-                  lib.generators.toLua { } { inherit (keybind.action) workspace; }
+                focus = "hl.dsp.focus(${
+                  lib.generators.toLua { } { inherit (keybind.action) direction workspace; }
                 })";
               }
               .${keybind.action.kind}