Add playlist_url property to GPUHLSOutput

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

streaming/gpu_output.py

@@ -386,3 +386,10 @@ class GPUHLSOutput:
     @property
     def playlist_cid(self) -> Optional[str]:
         return self._playlist_cid
+
+    @property
+    def playlist_url(self) -> Optional[str]:
+        """Get the full IPFS URL for the playlist."""
+        if self._playlist_cid:
+            return f"{self.ipfs_gateway}/{self._playlist_cid}"
+        return None