fix: restore native FLV reconnect with curl fallback

src/LiveRecorder.Infrastructure/Services/FfmpegService.cs

@@ -304,7 +304,8 @@ public sealed partial class FfmpegService : IFfmpegService
                      streamUrlResult.SelectedProtocol,
                      streamUrlResult.SelectedVideoCodec,
                      recoveryContext.InputOptionProfile,
-                     recoveryVideoEncoder))
+                     recoveryVideoEncoder,
+                     recoveryContext.UseCurlFallback))
         {
             process.StartInfo.ArgumentList.Add(argument);
         }
@@ -326,11 +327,13 @@ public sealed partial class FfmpegService : IFfmpegService
             throw new InvalidOperationException("A running ffmpeg process already exists for the recording session.");
         }
 
-        // When the stream URL is HTTP, launch curl to handle the HTTP connection and
-        // pipe its stdout into FFmpeg's stdin. This bypasses FFmpeg's built-in HTTP
-        // handler which has a hard-coded 4096-byte response header buffer that triggers
-        // "overlong headers" errors with CDNs that return oversized headers.
-        if (ShouldUseCurlPipe(streamUrlResult.SelectedUrl, streamUrlResult.SelectedProtocol))
+        // curl is a one-shot compatibility fallback for native FLV inputs whose response
+        // headers exceed FFmpeg's built-in HTTP header limit. Normal FLV and all HLS
+        // inputs stay on FFmpeg's native HTTP stack so native reconnect remains active.
+        if (ShouldUseCurlPipe(
+                streamUrlResult.SelectedUrl,
+                streamUrlResult.SelectedProtocol,
+                recoveryContext.UseCurlFallback))
         {
             var curlProcess = new Process
             {
@@ -350,6 +353,14 @@ public sealed partial class FfmpegService : IFfmpegService
                 curlProcess.StartInfo.ArgumentList.Add(arg);
             }
 
+            curlProcess.Exited += (_, _) =>
+            {
+                _logger.LogInformation(
+                    "curl fallback connection ended for session {RecordSessionId} with exit code {ExitCode}.",
+                    recordSession.Id,
+                    runtime.CurlExitCode?.ToString() ?? "unknown");
+            };
+
             curlProcess.ErrorDataReceived += (_, args) =>
             {
                 if (!string.IsNullOrWhiteSpace(args.Data))
@@ -1451,7 +1462,7 @@ public sealed partial class FfmpegService : IFfmpegService
             SystemLogLevel.Info,
             "FFmpeg",
             $"ffmpeg input profile={runtime.InputOptionProfile}.",
-            detail: $"stream={runtime.SelectedProtocol}:{runtime.SelectedQuality}; videoCodec={runtime.SelectedVideoCodec ?? "unknown"}; recoveryEncoder={runtime.RecoveryVideoEncoder.Kind}; recoveryDevice={runtime.RecoveryVideoEncoder.DevicePath ?? "default"}; attempt={runtime.RetryAttemptCount}; compatibilityRetry={runtime.HasRetriedWithCompatibilityProfile}; refreshRetry={runtime.HasRetriedWithRefreshedStream}; alternateProtocolRetry={runtime.HasRetriedWithAlternateProtocol}; softwareEncoderRetry={runtime.RecoveryContext.HasRetriedWithSoftwareEncoder}",
+            detail: $"stream={runtime.SelectedProtocol}:{runtime.SelectedQuality}; inputTransport={(runtime.RecoveryContext.UseCurlFallback ? "curl-fallback" : "native-http")}; nativeReconnect={(runtime.RecordingSettings.EnableAutoReconnect && !runtime.RecoveryContext.UseCurlFallback ? "enabled" : "disabled")}; videoCodec={runtime.SelectedVideoCodec ?? "unknown"}; recoveryEncoder={runtime.RecoveryVideoEncoder.Kind}; recoveryDevice={runtime.RecoveryVideoEncoder.DevicePath ?? "default"}; attempt={runtime.RetryAttemptCount}; compatibilityRetry={runtime.HasRetriedWithCompatibilityProfile}; refreshRetry={runtime.HasRetriedWithRefreshedStream}; alternateProtocolRetry={runtime.HasRetriedWithAlternateProtocol}; curlFallbackTried={runtime.RecoveryContext.HasTriedCurlFallback}; softwareEncoderRetry={runtime.RecoveryContext.HasRetriedWithSoftwareEncoder}",
             liveRoomId: runtime.LiveRoomId,
             recordSessionId: runtime.RecordSessionId,
             recordTaskId: runtime.CurrentTaskId,