fix: 修复自编码模式黑屏问题

- 调整包序号过期检查逻辑，避免同一帧分片被误删
- 适配 Android 14，在创建 VirtualDisplay 前注册 MediaProjection.Callback
- 启动后检查编码器实际运行状态，失败时进行清理

WebRTCControlled/app/src/main/java/com/ttstd/controlled/service/ScreenCaptureService.java

@@ -476,6 +476,13 @@ public class ScreenCaptureService extends Service {
                     }
                 });
         selfEncoder.start();
+        // start() 内部捕获异常后 running 仍为 false，需据此判断真实启动结果，
+        // 否则会误报 SELF_CODEC 模式已生效而实际无任何画面（黑屏）。
+        if (!selfEncoder.isRunning()) {
+            Log.e(TAG, "self codec encoder failed to start, cleaning up");
+            stopSelfCodecEncoder();
+            return false;
+        }
         return true;
     }
 

WebRTCControlled/app/src/main/java/com/ttstd/controlled/webrtc/SelfCodecEncoder.java

@@ -45,6 +45,7 @@ public class SelfCodecEncoder {
     private MediaCodec encoder;
     private Surface inputSurface;
     private VirtualDisplay virtualDisplay;
+    private MediaProjection.Callback projectionCallback;
     private boolean running = false;
     private int frameSeq = 0;
     private final Object sendLock = new Object();
@@ -88,6 +89,20 @@ public class SelfCodecEncoder {
             inputSurface = encoder.createInputSurface();
             encoder.start();
 
+            // Android 14+ (API 34) 强制要求：在 createVirtualDisplay 之前必须先注册
+            // MediaProjection.Callback，否则会抛
+            // IllegalStateException("Must register a callback before starting capture...")，
+            // 导致自编码模式无法启动、控制端黑屏。onStop 时释放资源。
+            projectionCallback = new MediaProjection.Callback() {
+                @Override
+                public void onStop() {
+                    Log.e(TAG, "MediaProjection stopped, releasing encoder");
+                    release();
+                    if (callback != null) callback.onEncoderError("MediaProjection stopped");
+                }
+            };
+            mediaProjection.registerCallback(projectionCallback, null);
+
             virtualDisplay = mediaProjection.createVirtualDisplay(
                     "SelfCodec", width, height, dpi,
                     DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR, inputSurface, null, null);
@@ -246,6 +261,11 @@ public class SelfCodecEncoder {
         }
     }
 
+    /** 返回编码器是否正在运行（供上层判断启动结果）。 */
+    public boolean isRunning() {
+        return running;
+    }
+
     /** 即时请求一个关键帧（强求 IDR）。 */
     public void requestKeyFrame() {
         if (encoder == null) return;
@@ -260,6 +280,13 @@ public class SelfCodecEncoder {
 
     public void release() {
         running = false;
+        if (mediaProjection != null && projectionCallback != null) {
+            try {
+                mediaProjection.unregisterCallback(projectionCallback);
+            } catch (Exception ignored) {
+            }
+            projectionCallback = null;
+        }
         if (virtualDisplay != null) {
             try {
                 virtualDisplay.release();