feat: persist and expose resolvedEndpointUri for execution-level drill-down

Wire resolvedEndpointUri through the full chain:
- V9 migration adds resolved_endpoint_uri column
- IngestionService extracts from ProcessorExecution
- PostgresExecutionStore persists and reads the column
- ProcessorNode includes field in detail API response
- UI schema updated for ProcessorNode and PositionedNode

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

ui/src/api/schema.d.ts

@@ -1652,6 +1652,7 @@ export interface components {
             attributes: {
                 [key: string]: string;
             };
+            resolvedEndpointUri?: string;
             children: components["schemas"]["ProcessorNode"][];
         };
         DiagramLayout: {
@@ -1680,6 +1681,7 @@ export interface components {
             width?: number;
             /** Format: double */
             height?: number;
+            endpointUri?: string;
         };
         /** @description OIDC configuration for SPA login flow */
         OidcPublicConfigResponse: {