Options regrouped: session.*, keyboard.*, launcherMenu.hiddenApps

- runtimeDir, userBus, outerBusEnv, userServices.*, portalFix.enable
  -> session.{runtimeDir, bus, busEnv, services.*, portalFix.enable}
- keyboardLayout/keyboardVariant -> keyboard.layout/variant;
  steamKeyboardPatch.enable -> keyboard.vr.extraKeys.enable
- hiddenApps -> launcherMenu.hiddenApps
- launcherMenu.launchDebounce -> launchDebounceSeconds (also the patch's
  option key; launcher-menu-launch VERSION 3)
- "Steam UI patch" in option descriptions

Old names keep working with a rename warning (outerBusEnv is read-only:
reading it warns).

modules/hidden-apps.nix

@@ -1,15 +1,23 @@
 # Hide desktop entries from the "+" menu and the KDE menu: a user entry with
 # Hidden=true masks the system one.
 { config, lib, ... }: {
-  options.steamFrame.hiddenApps = lib.mkOption {
+  imports = [
+    (lib.mkRenamedOptionModule
+      [ "steamFrame" "hiddenApps" ] [ "steamFrame" "launcherMenu" "hiddenApps" ])
+  ];
+
+  options.steamFrame.launcherMenu.hiddenApps = lib.mkOption {
     type = lib.types.listOf lib.types.str;
     default = [ ];
     example = [ "lxterminal" "cmake-gui" "firewall-config" "renderdoc" ];
-    description = "Desktop entry ids (without .desktop) to hide from the \"+\" menu and the KDE menu.";
+    description = ''
+      Desktop entry ids (without .desktop) to hide from the "+" menu and the
+      KDE menu.
+    '';
   };
 
   config.xdg.dataFile = lib.genAttrs
-    (map (id: "applications/${id}.desktop") config.steamFrame.hiddenApps)
+    (map (id: "applications/${id}.desktop") config.steamFrame.launcherMenu.hiddenApps)
     (_: {
       text = ''
         [Desktop Entry]