fix(ios): adopt FlutterSceneLifeCycleDelegate for UIScene deep link support

The plugin only implemented AppDelegate-based lifecycle methods for deep
linking. Since Flutter 3.41 auto-migrates apps to UIScene by default,
UIKit no longer calls application:openURL:options: or
application:continueUserActivity: — routing everything through the scene
delegate instead. This caused deep links to be silently dropped on iOS
apps using Flutter 3.41+.

Fix:
- Adopt FlutterSceneLifeCycleDelegate in AppsflyerSdkPlugin
- Register via [registrar addSceneDelegate:instance] (iOS 13+)
- Add scene:openURLContexts: for warm-start URI-scheme deep links
- Add scene:willConnectToSession:options: for cold-start URI-scheme deep links
- Add scene:continueUserActivity: for Universal Links via UIScene

Verified on iOS 18.4 simulator with Flutter 3.41.4. Both cold-start and
warm-start deep link callbacks now reach the plugin correctly without
requiring any app-side workaround.

Fixes: DELIVERY-114618

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

Author: Kobikg78

ios/Classes/AppsflyerSdkPlugin.h

@@ -6,7 +6,7 @@
 #import "AppsFlyerLib.h"
 #endif
 
-@interface AppsflyerSdkPlugin: NSObject<FlutterPlugin>
+@interface AppsflyerSdkPlugin: NSObject<FlutterPlugin, FlutterSceneLifeCycleDelegate>
 
 @property (readwrite, nonatomic) BOOL isManualStart;
 
@@ -18,7 +18,7 @@
 @end
 
 // Appsflyer JS objects
-#define kAppsFlyerPluginVersion             @"6.17.8"
+#define kAppsFlyerPluginVersion             @"6.17.9"
 #define afDevKey                            @"afDevKey"
 #define afAppId                             @"afAppId"
 #define afIsDebug                           @"isDebug"

ios/Classes/AppsflyerSdkPlugin.m

@@ -68,7 +68,9 @@ + (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar>*)registrar {
     [registrar addMethodCallDelegate:instance channel:channel];
     [registrar addMethodCallDelegate:instance channel:callbackChannel];
     [registrar addApplicationDelegate:instance];
-    
+    if (@available(iOS 13.0, *)) {
+        [registrar addSceneDelegate:instance];
+    }
 
 }
 
@@ -947,10 +949,36 @@ - (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceAppl
 // Open Universal Links
 - (BOOL)application:(UIApplication *)application continueUserActivity:(NSUserActivity *)userActivity restorationHandler:(void (^)(NSArray * _Nullable))restorationHandler {
     [[AppsFlyerAttribution shared] continueUserActivity:userActivity restorationHandler:restorationHandler];
-    
+
     // Results of this are ORed and NO doesn't affect other delegate interceptors' result.
     return NO;
 }
 
+#pragma mark - FlutterSceneLifeCycleDelegate
+
+// UIScene-based URI-scheme deep links (iOS 13+, Flutter 3.41+ UIScene migration)
+- (BOOL)scene:(UIScene*)scene openURLContexts:(NSSet<UIOpenURLContext*>*)URLContexts API_AVAILABLE(ios(13.0)) {
+    for (UIOpenURLContext *context in URLContexts) {
+        [[AppsFlyerAttribution shared] handleOpenUrl:context.URL options:@{}];
+    }
+    return NO;
+}
+
+// Cold-start URI-scheme deep links delivered via UISceneConnectionOptions (iOS 13+)
+- (BOOL)scene:(UIScene*)scene
+    willConnectToSession:(UISceneSession*)session
+                 options:(UISceneConnectionOptions*)connectionOptions API_AVAILABLE(ios(13.0)) {
+    for (UIOpenURLContext *context in connectionOptions.URLContexts) {
+        [[AppsFlyerAttribution shared] handleOpenUrl:context.URL options:@{}];
+    }
+    return NO;
+}
+
+// UIScene-based Universal Links (iOS 13+)
+- (BOOL)scene:(UIScene*)scene continueUserActivity:(NSUserActivity*)userActivity API_AVAILABLE(ios(13.0)) {
+    [[AppsFlyerAttribution shared] continueUserActivity:userActivity restorationHandler:nil];
+    return NO;
+}
+
 
 @end