fix(graph): NS, MX and web names share one column so edges do not cross nodes

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

zmtools/graph.py

@@ -52,6 +52,8 @@ def build(domain):
         nodes[zone_node]['nxdomain'] = True
         return {'domain': domain, 'nodes': list(nodes.values()), 'edges': edges,
                 'delegation': steps}
+    # Columns after the zone: names it publishes (NS, MX, www), CNAME targets,
+    # addresses, networks. Empty columns are collapsed by the GUI.
     L_REC, L_HOST, L_IP, L_NET = depth + 1, depth + 2, depth + 3, depth + 4
 
     ns = [n.rstrip('.') for n in dnsutil.resolve(domain, 'NS')]
@@ -68,13 +70,13 @@ def build(domain):
         host_ips[h] = ips
 
     for n in ns[:8]:
-        hid = node('host:' + n, n, 'ns', L_HOST)
+        hid = node('host:' + n, n, 'ns', L_REC)
         edge(zone_node, hid, 'NS')
     for pref, h in mx[:6]:
         h = h.rstrip('.')
         if h in ('', '.'):
             continue
-        hid = node('host:' + h, h, 'mx', L_HOST, pref=int(pref))
+        hid = node('host:' + h, h, 'mx', L_REC, pref=int(pref))
         edge(zone_node, hid, f'MX {pref}')
 
     chains = dict(_pool.map(lambda w: (w, dnsutil.cname_chain(w)), web))
@@ -87,7 +89,7 @@ def build(domain):
             edge(zone_node, wid, None)
         cur = wid
         for i, target in enumerate(chains[w]):
-            tid = node('host:' + target, target, 'cname', L_HOST if i == len(chains[w]) - 1 else L_REC)
+            tid = node('host:' + target, target, 'cname', L_HOST)
             edge(cur, tid, 'CNAME')
             cur = tid
         if chains[w]: