Add local test data, implement [id].tsx for approval workflows

src/hooks/useApprovalWorkflows.tsx

@@ -5,7 +5,7 @@ import { useCallback, useEffect, useState } from "react";
 import approvalWorkflowsData from '../demo/approval_workflows.json' // to test locally
 
 export default function useApprovalWorkflows() {
-  const [approvalWorkflows, setApprovalWorkflows] = useState<ApprovalWorkflow[]>(approvalWorkflowsData);
+  const [approvalWorkflows, setApprovalWorkflows] = useState<ApprovalWorkflow[]>(approvalWorkflowsData as ApprovalWorkflow[]);
   const [isLoading, setIsLoading] = useState(false);
   const [isError, setIsError] = useState(false);