feat(dataflow): add OpenMetadata governance node + catalog edges + UI link

Data Flow graph now shows OpenMetadata as a governance node linked to all
sources and Trino (catalog edges); node inspector exposes an 'Open in
OpenMetadata' deep link and PII-columns-cataloged metric.

ui/src/components/features/DataFlowView.tsx

@@ -15,6 +15,7 @@ const NODE_KIND: Record<string, { ring: string; chip: string; dot: string }> = {
   sink: { ring: 'border-sky-400/60', chip: 'bg-sky-500/15 text-sky-300 border-sky-400/40', dot: '#38bdf8' },
   lakehouse: { ring: 'border-blue-400/60', chip: 'bg-blue-500/15 text-blue-300 border-blue-400/40', dot: '#60a5fa' },
   engine: { ring: 'border-violet-400/60', chip: 'bg-violet-500/15 text-violet-300 border-violet-400/40', dot: '#a78bfa' },
+  governance: { ring: 'border-fuchsia-400/60', chip: 'bg-fuchsia-500/15 text-fuchsia-300 border-fuchsia-400/40', dot: '#d946ef' },
 }
 
 const EDGE_COLOR: Record<string, string> = {
@@ -24,6 +25,7 @@ const EDGE_COLOR: Record<string, string> = {
   movement: '#a78bfa',
   mask: '#fb7185',
   query: '#818cf8',
+  catalog: '#d946ef',
 }
 
 const EDGE_LEGEND: { kind: string; label: string }[] = [
@@ -33,6 +35,7 @@ const EDGE_LEGEND: { kind: string; label: string }[] = [
   { kind: 'movement', label: 'ETL movement' },
   { kind: 'mask', label: 'PII masking' },
   { kind: 'query', label: 'Query' },
+  { kind: 'catalog', label: 'Catalog (OpenMetadata)' },
 ]
 
 type Anchor = { x: number; y: number; w: number; h: number }
@@ -314,6 +317,16 @@ export function DataFlowView() {
             {selNode.metric && (
               <p className="mt-1 font-mono text-[8px] text-emerald-300">{selNode.metric}</p>
             )}
+            {selNode.url && (
+              <a
+                href={selNode.url}
+                target="_blank"
+                rel="noreferrer"
+                className="mt-1 inline-block rounded border border-fuchsia-400/40 bg-fuchsia-500/15 px-1.5 py-0.5 text-[8px] font-medium text-fuchsia-200 hover:bg-fuchsia-500/25"
+              >
+                Open in OpenMetadata ↗
+              </a>
+            )}
             {selNode.pii?.has_pii ? (
               <div className="mt-1.5 border-t border-border pt-1.5">
                 <div className="mb-1 flex items-center gap-1 text-[9px] font-medium text-rose-300">