fix: handle non-array action and intent-filter in AndroidManifest parsing

XML parsers like xml2js (used by @expo/config-plugins) may return a single
object instead of an array when there is only one child element. The
hasExistingFcmService check assumed action and intent-filter were always
arrays, causing a TypeError on Expo SDK 55 for versions > 9.6.3.

Normalize both fields with [].concat() before calling .some() so the check
works regardless of whether the XML parser returns an object or an array.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: Your Name

__tests__/withAndroidPushNotifications.test.ts

@@ -351,6 +351,70 @@ dependencies {
 
       warnSpy.mockRestore();
     });
+
+    test('detects existing FCM service when action is a single object (not array)', () => {
+      const config = createMockConfig('com.example.myapp');
+      const warnSpy = jest.spyOn(console, 'warn').mockImplementation();
+
+      config.modResults.manifest.application[0].service.push({
+        '$': {
+          'android:name': '.ExistingFcmService',
+          'android:exported': 'true',
+        },
+        'intent-filter': [
+          {
+            action: {
+              $: {
+                'android:name': 'com.google.firebase.MESSAGING_EVENT',
+              },
+            },
+          },
+        ],
+      } as any);
+
+      withAndroidPushNotifications(config as any, {} as any);
+
+      const services = config.modResults.manifest.application[0].service;
+      expect(services).toHaveLength(1);
+      expect(services[0].$['android:name']).toBe('.ExistingFcmService');
+      expect(warnSpy).toHaveBeenCalledWith(
+        expect.stringContaining('existing FirebaseMessagingService')
+      );
+
+      warnSpy.mockRestore();
+    });
+
+    test('detects existing FCM service when intent-filter is a single object (not array)', () => {
+      const config = createMockConfig('com.example.myapp');
+      const warnSpy = jest.spyOn(console, 'warn').mockImplementation();
+
+      config.modResults.manifest.application[0].service.push({
+        '$': {
+          'android:name': '.ExistingFcmService',
+          'android:exported': 'true',
+        },
+        'intent-filter': {
+          action: [
+            {
+              $: {
+                'android:name': 'com.google.firebase.MESSAGING_EVENT',
+              },
+            },
+          ],
+        },
+      } as any);
+
+      withAndroidPushNotifications(config as any, {} as any);
+
+      const services = config.modResults.manifest.application[0].service;
+      expect(services).toHaveLength(1);
+      expect(services[0].$['android:name']).toBe('.ExistingFcmService');
+      expect(warnSpy).toHaveBeenCalledWith(
+        expect.stringContaining('existing FirebaseMessagingService')
+      );
+
+      warnSpy.mockRestore();
+    });
   });
 
   describe('error handling', () => {

src/expo-plugins/withAndroidPushNotifications.ts

@@ -152,13 +152,18 @@ const registerServiceInManifest: ConfigPlugin<IntercomPluginProps> = (
     const hasExistingFcmService = mainApplication.service?.some(
       (s) =>
         s.$?.['android:name'] !== serviceName &&
-        s['intent-filter']?.some(
-          (f: any) =>
-            f.action?.some(
-              (a: any) =>
-                a.$?.['android:name'] === 'com.google.firebase.MESSAGING_EVENT'
-            )
-        )
+        ([] as any[])
+          .concat(s['intent-filter'] ?? [])
+          .some(
+            (f: any) =>
+              ([] as any[])
+                .concat(f.action ?? [])
+                .some(
+                  (a: any) =>
+                    a.$?.['android:name'] ===
+                    'com.google.firebase.MESSAGING_EVENT'
+                )
+          )
     );
 
     if (hasExistingFcmService) {