add(nixos): input method

apps/hyprland/hypr/exec.nix

@@ -9,6 +9,7 @@
     ];
     exec-once = [
       "hyprpm reload -n"
+      "fcitx5 -d --replace"
       "[workspace special:preload silent] uwsm app -- firefox"
       "[workspace special:preload silent] uwsm app -- firefox -P YouTube"
       "[workspace special:preload silent] uwsm app -- xdg-terminal-exec"

modules/nixos/default.nix

@@ -15,6 +15,7 @@
     ./security.nix
     ./variables.nix
     ./kernel.nix
+    ./input-method.nix
   ];
   environment.systemPackages = with pkgs; [
     # FIXME: must be on their own app

modules/nixos/input-method.nix

@@ -0,0 +1,13 @@
+{pkgs, ...}: {
+  i18n.inputMethod = {
+    enable = true;
+    type = "fcitx5";
+    fcitx5 = {
+      waylandFrontend = true;
+      addons = with pkgs; [
+        fcitx5-mozc
+        fcitx5-gtk
+      ];
+    };
+  };
+}