✨ Add StreamType for multi-client support and improved UPnP control

- Introduce `Streamtype` enum (Continuous vs Finite) to distinguish radio streams from finite tracks
- Enrich `TrackBoundary` sync marker with stream type for proper pause behavior per mode (silence vs backpressure)
- Update all sources and sinks to pass `StreamType` when creating track boundaries
  - Radio Paradise, HTTP source → Continuous (infinite)
- Improve UPnP control architecture: pause sends silence for radio, blocks pipeline via backpressure for tracks
- Prepare groundwork for multi-client DSP architecture with shared source and per-DSP pipelines

pmoaudio-ext/src/sinks/flac_cache_sink.rs

@@ -233,7 +233,7 @@ impl NodeLogic for FlacCacheSinkLogic {
                                         }
                                     }
                                     _AudioSegment::Sync(marker) => match &**marker {
-                                        SyncMarker::TrackBoundary { metadata } => {
+                                        SyncMarker::TrackBoundary { metadata, .. } => {
                                             // TrackBoundary pendant le prebuffer - track courte (< 512KB)
                                             tracing::warn!(
                                                 "FlacCacheSink: TrackBoundary received before prebuffer complete - track shorter than 512KB, closing pump and waiting for ingestion"
@@ -589,7 +589,7 @@ impl NodeLogic for FlacCacheSinkLogic {
                         // Si pump_closed, ignorer silencieusement le chunk
                     }
                     _AudioSegment::Sync(marker) => match &**marker {
-                        SyncMarker::TrackBoundary { metadata } => {
+                        SyncMarker::TrackBoundary { metadata, .. } => {
                             // Nouveau morceau - fermer le pump si pas déjà fermé
                             tracing::debug!("FlacCacheSink: TrackBoundary received, closing pump and storing metadata for next track");
                             // Stocker les métadonnées pour la prochaine track

pmoaudio-ext/src/sinks/streaming_flac_sink.rs

@@ -307,7 +307,7 @@ impl NodeLogic for StreamingFlacSinkLogic {
 
                                 _AudioSegment::Sync(marker) => {
                                     match marker.as_ref() {
-                                        SyncMarker::TrackBoundary { metadata } => {
+                                        SyncMarker::TrackBoundary { metadata, .. } => {
                                             // Prepare encoder options (metadata + duration) for the upcoming track.
                                             if let Err(e) =
                                                 self.ctx.prepare_encoder_options_for_track(metadata).await

pmoaudio-ext/src/sinks/streaming_icyflac_sink.rs

@@ -88,8 +88,17 @@ impl IcyClientStream {
 
         // Add cover URL if we have a cover_pk
         if let Some(pk) = &meta.cover_pk {
+            #[cfg(feature = "playlist")]
             let cover_url = pmocache::covers_absolute_url_for_upnp(pk, None);
-            metadata_str.push_str(&format!("StreamUrl='{}';", cover_url));
+            #[cfg(feature = "playlist")]
+            {
+                metadata_str.push_str(&format!("StreamUrl='{}';", cover_url));
+            }
+            #[cfg(not(feature = "playlist"))]
+            {
+                // When playlist feature is not enabled, use relative URL
+                metadata_str.push_str(&format!("StreamUrl='/covers/image/{}/256';", pk));
+            }
         } else if let Some(url) = &meta.cover_url {
             // Fallback to external cover URL if no local pk
             metadata_str.push_str(&format!("StreamUrl='{}';", url));

pmoaudio-ext/src/sinks/streaming_ogg_flac_sink.rs

@@ -265,7 +265,7 @@ impl NodeLogic for StreamingOggFlacSinkLogic {
 
                                 _AudioSegment::Sync(marker) => {
                                     match marker.as_ref() {
-                                        SyncMarker::TrackBoundary { metadata } => {
+                                        SyncMarker::TrackBoundary { metadata, .. } => {
                                             // Inject per-track metadata and duration into the next FLAC header.
                                             if let Err(e) =
                                                 self.ctx.prepare_encoder_options_for_track(metadata).await

pmoaudio-ext/src/sources/player_source.rs

@@ -35,6 +35,7 @@ use pmoaudio::{
     AudioSegment,
     nodes::AudioError,
     pipeline::{AudioPipelineNode, Node, NodeLogic, send_to_children},
+    StreamType,
 };
 use tokio::sync::{broadcast, mpsc};
 use tokio_util::sync::CancellationToken;
@@ -505,7 +506,7 @@ async fn send_track_boundary(
         let _ = meta.set_title(Some(u.to_string())).await;
     }
     let meta_arc = Arc::new(tokio::sync::RwLock::new(meta));
-    let boundary = AudioSegment::new_track_boundary(0, timestamp_sec, meta_arc);
+    let boundary = AudioSegment::new_track_boundary(0, timestamp_sec, meta_arc, StreamType::Finite);
 
     send_to_children("PlayerSource", output, boundary).await
 }

pmoaudio-ext/src/sources/playlist_source.rs

@@ -113,7 +113,7 @@ use pmoaudio::{
     nodes::{AudioError, TypedAudioNode, DEFAULT_CHUNK_DURATION_MS},
     pipeline::{send_to_children, AudioPipelineNode, Node, NodeLogic},
     type_constraints::TypeRequirement,
-    AudioSegment,
+    AudioSegment, StreamType,
 };
 use pmoaudiocache::Cache as AudioCache;
 use pmoflac::decode_audio_stream;
@@ -279,7 +279,7 @@ impl NodeLogic for PlaylistSourceLogic {
             let track_start = std::time::Instant::now();
             tracing::debug!("PlaylistSourceLogic: emitting TrackBoundary");
             let metadata_for_boundary = metadata.clone();
-            let boundary = AudioSegment::new_track_boundary(0, 0.0, metadata_for_boundary);
+            let boundary = AudioSegment::new_track_boundary(0, 0.0, metadata_for_boundary, StreamType::Finite);
             send_to_children(node_name, &output, boundary).await?;
 
             // Obtenir le chemin du fichier