Add country dropdown selector to login screens of siro_service and siro_admin

siro_service/lib/controller/login_controller.dart

@@ -21,6 +21,13 @@ class LoginController extends GetxController {
 
   final FlutterSecureStorage storage = const FlutterSecureStorage();
 
+  var selectedCountry = 'Jordan'.obs;
+
+  void changeCountry(String country) {
+    selectedCountry.value = country;
+    box.write(BoxName.countryCode, country);
+  }
+
   void login() async {
     // Ensure fingerprint is ready
     String fingerprint = box.read(BoxName.fingerPrint) ?? '';
@@ -177,6 +184,7 @@ class LoginController extends GetxController {
 
   @override
   void onInit() async {
+    selectedCountry.value = box.read(BoxName.countryCode) ?? 'Jordan';
     await EncryptionHelper.initialize();
     await DeviceHelper.getDeviceFingerprint();
 

siro_service/lib/login_page.dart

@@ -100,7 +100,36 @@ class LoginPage extends StatelessWidget {
                       hint: 'أدخل كلمة المرور',
                       type: TextInputType.visiblePassword,
                     ),
-                    
+                    const SizedBox(height: 20),
+
+                    Obx(() => Container(
+                          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
+                          decoration: BoxDecoration(
+                            color: Colors.grey.withOpacity(0.08),
+                            borderRadius: BorderRadius.circular(16),
+                            border: Border.all(color: Colors.grey.withOpacity(0.2)),
+                          ),
+                          child: DropdownButtonHideUnderline(
+                            child: DropdownButton<String>(
+                              value: controller.selectedCountry.value,
+                              icon: const Icon(Icons.arrow_drop_down, color: AppColor.blueColor),
+                              isExpanded: true,
+                              dropdownColor: Colors.white,
+                              style: const TextStyle(color: Colors.black87, fontSize: 16),
+                              items: ['Jordan', 'Egypt', 'Syria'].map((String country) {
+                                return DropdownMenuItem<String>(
+                                  value: country,
+                                  child: Text(country.tr),
+                                );
+                              }).toList(),
+                              onChanged: (String? val) {
+                                if (val != null) {
+                                  controller.changeCountry(val);
+                                }
+                              },
+                            ),
+                          ),
+                        )),
                     const SizedBox(height: 40),
 
                     // Login Button