propagation: single registry drives all node references

New bin/netvm-registry.py parses NODES.md (node -> cdp_port); every
consumer reads from it instead of hardcoding:
- onboard-driver.py: CDP_PORTS dict -> registry lookup (new nodes work)
- muse-signin.py: hardcoded 9410 -> --node/--cdp-port args
- muse-chat-api.py: hardcoded ACCOUNTS -> registry-built
- agent-health.sh: hardcoded muse/pip blocks -> loop over all active
  nodes (646 and opm now get health coverage too)
NODES.md: record opm node (9440).

bin/muse-chat-api.py

@@ -16,14 +16,24 @@ Usage:
   muse-chat-api.py --account <agent> wait [timeout]
   muse-chat-api.py --account <agent> approvals  # check pending approvals
 """
-import json, urllib.request, websocket, time, sys, argparse
+import json, urllib.request, websocket, time, sys, argparse, importlib.util
 
-ACCOUNTS = {
-    "muse": ("muse", "http://127.0.0.1:9410/json/list"),
-    "pip": ("pip", "http://127.0.0.1:9420/json/list"),
-    "646": ("646", "http://127.0.0.1:9430/json/list"),
-    "opm": ("opm", "http://127.0.0.1:9440/json/list"),
-}
+
+def _load_accounts():
+    """Build the accounts table from the NODES.md registry — new nodes
+    propagate automatically instead of being hardcoded here."""
+    path = "/home/super/Projects/NetVM/bin/netvm-registry.py"
+    spec = importlib.util.spec_from_file_location("netvm_registry", path)
+    mod = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(mod)
+    accounts = {}
+    for node, rec in mod.load().items():
+        accounts[node] = (node, "http://127.0.0.1:%d/json/list" %
+                          rec["cdp_port"])
+    return accounts
+
+
+ACCOUNTS = _load_accounts()
 
 # IPs we trust for auto-approval (our infrastructure)
 TRUSTED_IPS = {