add retry for call messages

Session/Calls/Call Management/SessionCall.swift

@@ -256,10 +256,25 @@ public final class SessionCall: CurrentCallProtocol, WebRTCSessionDelegate {
                 interactionId: interaction?.id,
                 in: thread
             )
+            .retry(5)
             // Start the timeout timer for the call
             .handleEvents(receiveOutput: { [weak self] _ in self?.setupTimeoutTimer() })
-            .flatMap { _ in webRTCSession.sendOffer(to: thread) }
-            .sinkUntilComplete()
+            .flatMap { _ in
+                webRTCSession
+                    .sendOffer(to: thread)
+                    .retry(5)
+            }
+            .sinkUntilComplete(
+                receiveCompletion: { [weak self] result in
+                    switch result {
+                        case .finished:
+                            SNLog("[Calls] Offer message sent")
+                        case .failure(let error):
+                            SNLog("[Calls] Error initializing call after 5 retries: \(error), ending call...")
+                            self?.handleCallInitializationFailed()
+                    }
+                }
+            )
     }
     
     func answerSessionCall() {
@@ -292,6 +307,11 @@ public final class SessionCall: CurrentCallProtocol, WebRTCSessionDelegate {
         hasEnded = true
     }
     
+    func handleCallInitializationFailed() {
+        self.endSessionCall()
+        Singleton.callManager.reportCurrentCallEnded(reason: nil)
+    }
+    
     // MARK: - Call Message Handling
     
     public func updateCallMessage(mode: EndCallMode, using dependencies: Dependencies) {

Session/Calls/WebRTC/WebRTCSession+MessageHandling.swift

@@ -22,7 +22,9 @@ extension WebRTCSession {
             else {
                 guard sdp.type == .offer else { return }
                 
-                self?.sendAnswer(to: sessionId).sinkUntilComplete()
+                self?.sendAnswer(to: sessionId)
+                    .retry(5)
+                    .sinkUntilComplete()
             }
         })
     }

Session/Calls/WebRTC/WebRTCSession.swift

@@ -375,6 +375,7 @@ public final class WebRTCSession : NSObject, RTCPeerConnectionDelegate {
         MessageSender
             .sendImmediate(data: preparedSendData, using: dependencies)
             .subscribe(on: DispatchQueue.global(qos: .userInitiated))
+            .retry(5)
             .sinkUntilComplete()
     }