chore: restore AndroidManifest/Info.plist changes + resolve stash conflicts

Merges in-progress manifest/plist changes (stashed before merge).
Resolves trivial comment conflicts in api_endpoints.dart and auth_service.dart —
both retained backend.eventifyplus.com URL and Google OAuth serverClientId.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

android/app/src/main/AndroidManifest.xml

@@ -18,6 +18,18 @@
             android:name="com.google.android.geo.API_KEY"
             android:value="YOUR_GOOGLE_MAPS_API_KEY"/>
 
+        <!-- Splash video plays first, then launches MainActivity -->
+        <activity
+            android:name=".SplashActivity"
+            android:exported="true"
+            android:theme="@android:style/Theme.Black.NoTitleBar.Fullscreen"
+            android:screenOrientation="portrait">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+
         <activity
             android:name=".MainActivity"
             android:exported="true"
@@ -31,11 +43,6 @@
             <meta-data
                 android:name="io.flutter.embedding.android.NormalTheme"
                 android:resource="@style/NormalTheme" />
-
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN" />
-                <category android:name="android.intent.category.LAUNCHER" />
-            </intent-filter>
         </activity>
 
         <!-- Don't delete the meta-data below. Used by Flutter tool. -->