Fix WS front wiring and AppDelegate keepalive task

- MTWebSocketConnectionInterface: use WebSocketFrontBootstrap.templates as default
  plan config so CF Worker fronts are picked up without SharedData round-trip
- AppDelegate: replace mutable-closure keepalive pattern with Box class to avoid
  variable-capture issue with UIBackgroundTaskIdentifier

Co-authored-by: D3C0Y <decoder-dev@users.noreply.github.com>

Author: decoder-dev

submodules/TelegramCore/Sources/Network/MTWebSocketConnectionInterface.swift

@@ -263,10 +263,12 @@ final class MTWebSocketConnectionInterface: NSObject, MTTcpConnectionInterface {
             self.isMediaConnection = isMediaConnection
             self.isTestingEnvironment = isTestingEnvironment
             self.fallbackCoordinator = fallbackCoordinator
+            let frontConfig = WebSocketEndpointPlanConfig(fronts: WebSocketFrontBootstrap.templates, order: .frontsFirst)
             self.endpointSelector = WebSocketEndpointSelector(candidates: WebSocketEndpointPlanner.candidates(
                 datacenterId: datacenterId,
                 isMedia: isMediaConnection,
-                isTestingEnvironment: isTestingEnvironment
+                isTestingEnvironment: isTestingEnvironment,
+                config: frontConfig
             ))
         }
 

submodules/TelegramUI/Sources/AppDelegate.swift

@@ -2086,16 +2086,20 @@ private func extractAccountManagerState(records: AccountRecordsView<TelegramAcco
         // Keep the WEB proxy carrier alive briefly in the background so the next foreground
         // resume can skip the carrier rebuild (avoids "Connecting" flicker). A single PING is
         // enough — the relay's own keep-alive timer runs on the server side.
-        var webProxyKeepaliveTaskId = UIBackgroundTaskIdentifier.invalid
-        let endWebProxyKeepaliveTask = { [application] in
-            let id = webProxyKeepaliveTaskId
-            webProxyKeepaliveTaskId = .invalid
-            if id != .invalid { application.endBackgroundTask(id) }
-        }
-        webProxyKeepaliveTaskId = application.beginBackgroundTask(withName: "web-proxy-keepalive", expirationHandler: endWebProxyKeepaliveTask)
-        DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {
+        final class Box { var value: UIBackgroundTaskIdentifier = .invalid }
+        let webProxyTaskBox = Box()
+        webProxyTaskBox.value = application.beginBackgroundTask(withName: "web-proxy-keepalive") { [weak webProxyTaskBox] in
+            if let box = webProxyTaskBox, box.value != .invalid {
+                application.endBackgroundTask(box.value)
+                box.value = .invalid
+            }
+        }
+        DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) { [weak webProxyTaskBox] in
             let _ = WebProxyManager.shared.sendKeepalivePing()
-            endWebProxyKeepaliveTask()
+            if let box = webProxyTaskBox, box.value != .invalid {
+                application.endBackgroundTask(box.value)
+                box.value = .invalid
+            }
         }
     }