fix(swift-sdk): handle integer size values in size-changed notifications

JSON integers are decoded as Int, not Double, but the code was casting
to Double which failed silently. Use NSNumber to handle both Int and
Double values from the JSON decoder.

Author: ochafik

swift/Sources/McpApps/AppBridge.swift

@@ -107,8 +107,9 @@ public actor AppBridge {
             isInitialized = true
             onInitialized?()
         case "ui/notifications/size-changed":
-            let width = notification.params?["width"]?.value as? Int
-            let height = notification.params?["height"]?.value as? Int
+            // Handle both Int and Double from JSON (integers decode as Int, not Double)
+            let width = (notification.params?["width"]?.value as? NSNumber)?.intValue
+            let height = (notification.params?["height"]?.value as? NSNumber)?.intValue
             onSizeChange?(width, height)
         case "notifications/message":
             if let level = notification.params?["level"]?.value as? String,