Fix UI types to match actual backend API

Validated against live OpenAPI spec at /api/v1/api-docs. Fixes:
- duration → durationMs (all models)
- Remove processorCount (not in ExecutionSummary)
- Remove ProcessorNode.index and .uri (not in backend)
- ProcessorSnapshot is Record<string,string>, not structured object
- Add missing fields: endTime, diagramContentHash, exchangeId, etc.
- Save openapi.json from live server

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

ui/src/pages/executions/ProcessorTree.tsx

@@ -35,8 +35,8 @@ export function ProcessorTree({ executionId }: { executionId: string }) {
   return (
     <div className={styles.tree}>
       <h4 className={styles.title}>Processor Execution Tree</h4>
-      {data.processors.map((proc) => (
-        <ProcessorNodeView key={proc.index} node={proc} />
+      {data.processors.map((proc, i) => (
+        <ProcessorNodeView key={proc.processorId ?? i} node={proc} />
       ))}
     </div>
   );
@@ -52,16 +52,15 @@ function ProcessorNodeView({ node }: { node: ProcessorNodeType }) {
         <div className={`${styles.procIcon} ${icon.className}`}>{icon.label}</div>
         <div className={styles.procInfo}>
           <div className={styles.procType}>{node.processorType}</div>
-          {node.uri && <div className={styles.procUri}>{node.uri}</div>}
         </div>
         <div className={styles.procTiming}>
-          <span className={styles.procDuration}>{node.duration}ms</span>
+          <span className={styles.procDuration}>{node.durationMs}ms</span>
         </div>
       </div>
       {node.children.length > 0 && (
         <div className={styles.nested}>
-          {node.children.map((child) => (
-            <ProcessorNodeView key={child.index} node={child} />
+          {node.children.map((child, i) => (
+            <ProcessorNodeView key={child.processorId ?? i} node={child} />
           ))}
         </div>
       )}