fix: use root tree for compound node detection instead of flat nodes list

The agent now sends shallow copies (without children) in the flat nodes
list. Build nodeById map by walking graph.getRoot() tree which preserves
children, falling back to flat list via putIfAbsent for compatibility.

Also adds EIP_FILTER, EIP_IDEMPOTENT_CONSUMER, EIP_RECIPIENT_LIST as
new compound container types per updated DIAGRAMS.md.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/components/ProcessDiagram/node-colors.ts

@@ -65,6 +65,7 @@ const COMPOUND_TYPES = new Set([
   'ON_EXCEPTION', 'ERROR_HANDLER',
   'ON_COMPLETION',
   'EIP_CIRCUIT_BREAKER', '_CB_MAIN', '_CB_FALLBACK',
+  'EIP_FILTER', 'EIP_IDEMPOTENT_CONSUMER', 'EIP_RECIPIENT_LIST',
 ]);
 
 const ERROR_COMPOUND_TYPES = new Set([