Made File.Handle a non-copyable struct in the library to adopt Swift 6.4.

Sources/PlaydateKit/Graphics/Classes/StreamPlayer.swift

@@ -8,8 +8,10 @@ extension Graphics {
     /// Wraps `LCDStreamPlayer`.
     public final class StreamPlayer {
         let pointer: OpaquePointer
-        /// Retains the active source so it outlives the stream.
+        /// Retains the active source so it outlives the stream. A file
+        /// handle is owned outright, as it cannot be shared.
         private var retainedSource: AnyObject?
+        private var retainedFile: File.Handle?
 
         public init() {
             pointer = streamAPI.pointee.newPlayer.unsafelyUnwrapped().unsafelyUnwrapped
@@ -24,22 +26,26 @@ extension Graphics {
             streamAPI.pointee.setBufferSize.unsafelyUnwrapped(pointer, Int32(video), Int32(audio))
         }
 
-        /// Streams from an open file.
-        public func setFile(_ file: File.Handle) {
-            retainedSource = file
+        /// Streams from an open file. The stream takes ownership of the
+        /// handle and closes it when the source changes or the stream is freed.
+        public func setFile(_ file: consuming File.Handle) {
             streamAPI.pointee.setFile.unsafelyUnwrapped(pointer, file.pointer)
+            retainedFile = consume file
+            retainedSource = nil
         }
 
         /// Streams from an HTTP connection.
         public func setHTTPConnection(_ connection: Network.HTTPConnection) {
-            retainedSource = connection
             streamAPI.pointee.setHTTPConnection.unsafelyUnwrapped(pointer, connection.pointer)
+            retainedSource = connection
+            retainedFile = nil
         }
 
         /// Streams from a TCP connection.
         public func setTCPConnection(_ connection: Network.TCPConnection) {
-            retainedSource = connection
             streamAPI.pointee.setTCPConnection.unsafelyUnwrapped(pointer, connection.pointer)
+            retainedSource = connection
+            retainedFile = nil
         }
 
         /// The player used for the stream's audio track. Owned by the stream.