Update IPFS playlist CID in database during streaming for live HLS

- Add on_playlist_update callback to IPFSHLSOutput
- Pass callback through StreamInterpreter to output
- Update database with playlist CID as segments are created
- Enables live HLS redirect to IPFS before rendering completes

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

streaming/output.py

@@ -645,6 +645,7 @@ class IPFSHLSOutput(Output):
         preset: str = "fast",
         audio_source: str = None,
         ipfs_gateway: str = "https://ipfs.io/ipfs",
+        on_playlist_update: callable = None,
     ):
         self.output_dir = Path(output_dir)
         self.output_dir.mkdir(parents=True, exist_ok=True)
@@ -653,6 +654,7 @@ class IPFSHLSOutput(Output):
         self.segment_duration = segment_duration
         self.ipfs_gateway = ipfs_gateway.rstrip("/")
         self._is_open = True
+        self._on_playlist_update = on_playlist_update  # Callback when playlist CID changes
 
         # Auto-detect NVENC
         if codec == "auto":
@@ -792,6 +794,12 @@ class IPFSHLSOutput(Output):
         if cid:
             self._playlist_cid = cid
             print(f"IPFS: playlist updated -> {cid} ({len(self.segment_cids)} segments)", file=sys.stderr)
+            # Notify callback (e.g., to update database for live HLS redirect)
+            if self._on_playlist_update:
+                try:
+                    self._on_playlist_update(cid)
+                except Exception as e:
+                    print(f"IPFS: playlist callback error: {e}", file=sys.stderr)
 
     def write(self, frame: np.ndarray, t: float):
         """Write frame to HLS stream and upload segments to IPFS."""