fix: run button is enabled when an operator is unconfigured (#3914)

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This PR fixes the run button is enabled when an operator is unconfigured
(#3192)

<img width="3144" height="1406" alt="image"
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/>

<img width="3040" height="1360" alt="image"
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/>

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Fixes #3192

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Manual test to ensure the reported behavior is fixed.

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No.

---------

Co-authored-by: Zuozhi Wang <[email protected]>

Author: AnzhiZhang

frontend/src/app/workspace/service/validation/validation-workflow.service.ts

@@ -134,13 +134,15 @@ export class ValidationWorkflowService {
   }
 
   private updateValidationState(operatorID: string, validation: Validation) {
-    this.operatorValidationStream.next({ validation, operatorID });
     if (!validation.isValid) {
       this.workflowErrors[operatorID] = validation;
     } else {
       delete this.workflowErrors[operatorID];
-      this.workflowValidationErrorStream.next({ errors: this.workflowErrors, workflowEmpty: this.workflowEmpty });
     }
+
+    // emit event to streams after updating workflowErrors to keep subscribers' view of the state consistent
+    this.operatorValidationStream.next({ validation, operatorID });
+    this.workflowValidationErrorStream.next({ errors: this.workflowErrors, workflowEmpty: this.workflowEmpty });
   }
 
   private checkIfWorkflowEmpty() {