fix(z-task-modal): fixed validation logic for employees, at least 1 employee is required

app/src/plugins/tm@modal/task/z-task-modal.vue

@@ -635,6 +635,8 @@ export default {
 
       if (!(await this.v$.$validate())) return;
       if (!employeesValid || !timeblocksValid) return;
+
+      return true;
     },
 
     async handleOnRemoveEmployee() {
@@ -757,28 +759,41 @@ export default {
         this.employeeValidations = [];
 
         if (this.subtask.id) {
-          if (this.subtask.employee && this.subtask.duration) return;
-
-          this.employeeValidations[0] = {};
-
-          if (!this.subtask.employee_id)
-            this.employeeValidations[0].employee = true;
-
-          if (!this.subtask.duration)
-            this.employeeValidations[0].duration = true;
+          // For existing subtasks, require both employee and duration
+          if (!this.subtask.employee_id || !this.subtask.duration) {
+            this.employeeValidations[0] = {
+              employee: !this.subtask.employee_id,
+              duration: !this.subtask.duration,
+            };
+          }
         } else {
-          // For new subtasks, only validate non-empty employee entries
+          // For new subtasks, require at least one employee with duration
+          let hasValidEmployee = false;
+
           this.subtask.employees.forEach((employee, index) => {
             // Skip validation if both id and duration are empty
-            if (!employee.id && !employee.duration) return;
+            if (!employee.id && !employee.duration) {
+              // If this is the first employee and no valid employee exists yet, show validation
+              if (index === 0 && !hasValidEmployee) {
+                this.employeeValidations[index] = {
+                  employee: true,
+                  duration: true,
+                };
+              }
+              return;
+            }
 
-            // Only validate if either id or duration is filled
+            // Validate if either id or duration is filled
             if (employee.id || employee.duration) {
-              this.employeeValidations[index] = {};
+              this.employeeValidations[index] = {
+                employee: !employee.id,
+                duration: !employee.duration,
+              };
 
-              if (!employee.id) this.employeeValidations[index].employee = true;
-              if (!employee.duration)
-                this.employeeValidations[index].duration = true;
+              // If both id and duration are present, mark as valid
+              if (employee.id && employee.duration) {
+                hasValidEmployee = true;
+              }
             }
           });
         }
@@ -855,7 +870,7 @@ export default {
     subtask: {
       handler(val) {
         if (this.editMode && !this.subtask?.id) {
-          const employees = val.employees.filter(
+          const employees = val?.employees?.filter(
             (employee) => employee?.id || employee?.duration,
           ) || [{}];