feat: add QR Generator launcher (#2941)

* feat: add QR Generator modal with auto-generate on input debounce

- QRGeneratorModal with dual-buffer sequential fade animation
- Auto-generate QR code on typing stop (200ms debounce)
- Clear text button on input field
- Escape key closes modal
- Register modal in PopoutService and AppSearchService
- Go backend for text QR code generation

* fix: add QR Generator toggle to Launcher DMS settings

* qr: also add qrg built in launcher plugin

---------

Co-authored-by: bbedward <bbedward@gmail.com>

quickshell/Services/PopoutService.qml

@@ -47,6 +47,8 @@ Singleton {
     property var wifiPasswordModalLoader: null
     property var wifiQRCodeModal: null
     property var wifiQRCodeModalLoader: null
+    property var qrGeneratorModal: null
+    property var qrGeneratorModalLoader: null
     property var polkitAuthModal: null
     property var polkitAuthModalLoader: null
     property var bluetoothPairingModal: null
@@ -891,6 +893,13 @@ Singleton {
             wifiQRCodeModal.show(ssid);
     }
 
+    function showQRGeneratorModal(initialText) {
+        if (qrGeneratorModalLoader)
+            qrGeneratorModalLoader.active = true;
+        if (qrGeneratorModal)
+            qrGeneratorModal.show(initialText || "");
+    }
+
     function showHiddenNetworkModal() {
         if (wifiPasswordModalLoader)
             wifiPasswordModalLoader.active = true;