Fix asset_type detection when recording runs from L1

Fetch media_type and ipfs_cid from L1's cache endpoint instead of
hardcoding asset_type to "video". This fixes images being incorrectly
displayed as videos.

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

server.py

@@ -1731,6 +1731,22 @@ async def record_run(req: RecordRunRequest, user: User = Depends(get_required_us
     if not output_hash:
         raise HTTPException(400, "Run has no output hash")
 
+    # Fetch media type from L1 cache
+    try:
+        cache_resp = requests.get(
+            f"{l1_url}/cache/{output_hash}",
+            headers={"Accept": "application/json"},
+            timeout=10
+        )
+        cache_resp.raise_for_status()
+        cache_info = cache_resp.json()
+        media_type = cache_info.get("media_type", "image")
+        ipfs_cid = cache_info.get("ipfs_cid")
+    except Exception as e:
+        logger.warning(f"Failed to fetch cache info from L1: {e}")
+        media_type = "image"  # Default fallback
+        ipfs_cid = None
+
     # Build provenance from run
     provenance = {
         "inputs": [{"content_hash": h} for h in run.get("inputs", [])],
@@ -1747,7 +1763,8 @@ async def record_run(req: RecordRunRequest, user: User = Depends(get_required_us
     return await _register_asset_impl(RegisterRequest(
         name=req.output_name,
         content_hash=output_hash,
-        asset_type="video",  # Could be smarter about this
+        ipfs_cid=ipfs_cid,
+        asset_type=media_type,  # Detected from L1 cache
         tags=["rendered", "l1"],
         metadata={"l1_server": l1_url, "l1_run_id": req.run_id},
         provenance=provenance