[iOS] Fix joining initial URL if app was closed

On iOS, if the app is closed the startup options are only passed as the
`launchOptions` dictionary of `applicationDidFinishLaunching`. Thus add a helper
method to be called from there by embedding applications so we can copy that
dictionary.

ios/app/src/AppDelegate.m

 
 -             (BOOL)application:(UIApplication *)application
   didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
-    return YES;
+    return [JitsiMeetView application:application
+        didFinishLaunchingWithOptions:launchOptions];
 }
 
 #pragma mark Linking delegate methods
 
--  (BOOL)application:(UIApplication *)application
-continueUserActivity:(NSUserActivity *)userActivity
-  restorationHandler:(void (^)(NSArray *restorableObjects))restorationHandler {
+-    (BOOL)application:(UIApplication *)application
+  continueUserActivity:(NSUserActivity *)userActivity
+    restorationHandler:(void (^)(NSArray *restorableObjects))restorationHandler {
     return [JitsiMeetView application:application
                  continueUserActivity:userActivity
                    restorationHandler:restorationHandler];

ios/sdk/src/JitsiMeetView.h

 
 @property (nonatomic) BOOL welcomePageEnabled;
 
++             (BOOL)application:(UIApplication *_Nonnull)application
+  didFinishLaunchingWithOptions:(NSDictionary *_Nonnull)launchOptions;
+
 +    (BOOL)application:(UIApplication * _Nonnull)application
   continueUserActivity:(NSUserActivity * _Nonnull)userActivity
     restorationHandler:(void (^ _Nullable)(NSArray * _Nullable))restorationHandler;

ios/sdk/src/JitsiMeetView.m

     @try {
         NSString *name
             = [NSString stringWithFormat:@"%@: %@",
-               RCTFatalExceptionName, error.localizedDescription];
+                        RCTFatalExceptionName,
+                        error.localizedDescription];
         NSString *message
             = RCTFormatError(error.localizedDescription, jsStackTrace, 75);
         [NSException raise:name format:@"%@", message];
 
 static RCTBridgeWrapper *bridgeWrapper;
 
+/**
+ * Copy of the {@code launchOptions} dictionary that the application was started
+ * with. It is required for the initial URL to be used if a (Universal) link was
+ * used to launch a new instance of the application.
+ */
+static NSDictionary *_launchOptions;
+
 /**
  * The {@code JitsiMeetView}s associated with their {@code ExternalAPI} scopes
  * (i.e. unique identifiers within the process).
  */
 static NSMapTable<NSString *, JitsiMeetView *> *views;
 
++             (BOOL)application:(UIApplication *)application
+  didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
+    // Store launch options, will be used when we create the bridge.
+    _launchOptions = [launchOptions copy];
+
+    return YES;
+}
+
 #pragma mark Linking delegate helpers
 // https://facebook.github.io/react-native/docs/linking.html
 
 /**
  * Internal initialization:
  *
- * - sets the backgroudn color
+ * - sets the background color
  * - creates the React bridge
  * - loads the necessary custom fonts
  * - registers a custom fatal error error handler for React
 
     dispatch_once(&dispatchOncePredicate, ^{
         // Initialize the static state of JitsiMeetView.
-        bridgeWrapper = [[RCTBridgeWrapper alloc] init];
+        bridgeWrapper
+            = [[RCTBridgeWrapper alloc] initWithLaunchOptions:_launchOptions];
         views = [NSMapTable strongToWeakObjectsMapTable];
 
         // Dynamically load custom bundled fonts.

ios/sdk/src/RCTBridgeWrapper.h

 
 @property (nonatomic, readonly, strong)  RCTBridge *bridge;
 
+- (instancetype)initWithLaunchOptions:(NSDictionary *)launchOptions;
+
 @end

ios/sdk/src/RCTBridgeWrapper.m

  */
 @implementation RCTBridgeWrapper
 
-- (instancetype)init {
+- (instancetype)initWithLaunchOptions:(NSDictionary *)launchOptions {
     self = [super init];
     if (self) {
-        _bridge = [[RCTBridge alloc] initWithDelegate:self launchOptions:nil];
+        _bridge
+            = [[RCTBridge alloc] initWithDelegate:self
+                                    launchOptions:launchOptions];
     }
 
     return self;