fix: bw/stats 404, gateway links, history crash

- swr.ts: remove useBandwidth(), drop bw from useDashboard()
- events/route.ts: skip bandwidth SSE (Kubo 0.28.0 unsupported)
- usage/page.tsx: remove getBWStats call + bw references
- helpers.ts: gatewayLink -> ipfs.maos.dedyn.io (subdomain only)
- upload/page.tsx: fix local gatewayLink (subdomain only)
- storage.ts: update default gatewayUrl, add defensive getHistory()

graphify-out/_query.py

@@ -0,0 +1,20 @@
+import json
+from pathlib import Path
+
+g = json.loads(Path('graphify-out/graph.json').read_text(encoding='utf-8'))
+nodes = g.get('nodes', [])
+edges = g.get('edges', [])
+print(f'Nodes: {len(nodes)}, Edges: {len(edges)}')
+
+communities = g.get('communities', g.get('clusters', {}))
+if communities:
+    print(f'Communities: {len(communities)}')
+
+# Show node labels and types
+for n in nodes[:40]:
+    nid = n.get('id', '?')
+    label = n.get('label', n.get('name', '?'))
+    ntype = n.get('type', n.get('node_type', '?'))
+    print(f'  {nid}: {label} [{ntype}]')
+if len(nodes) > 40:
+    print(f'  ... and {len(nodes)-40} more')