refactor(task-modal): enhance validation logic for concept tasks to support incomplete data

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

@@ -779,7 +779,8 @@ export default {
       this.$router.replace({ name: this.$route.name });
     },
 
-    async validateAllFields() {
+    async validateAllFields(concept = false) {
+      if (concept === false) {
         const employeesValid = await this._validateEmployees();
         const timeblocksValid = await this._validateTimeblocks();
 
@@ -787,6 +788,12 @@ export default {
         if (!employeesValid || !timeblocksValid) return;
 
         return true;
+      } else {
+        const employeesValid = await this._validateEmployees();
+        if (!employeesValid) return;
+
+        return true;
+      }
     },
 
     async handleOnRemoveEmployee() {
@@ -799,16 +806,18 @@ export default {
 
     async save(concept = false) {
       this.wasFormValidationTriggered = true;
-      if (!(await this.validateAllFields())) return;
+      if (!(await this.validateAllFields(concept))) return;
 
       this.subtask.description = this.$refs['description'].getHTML();
       this._mergeDeadlineTimeDate();
 
       try {
         this.isSaving = true;
-        this.subtask.deadline = moment(this.subtask.deadline).format(
-          'YYYY-MM-DD HH:mm:SS',
-        );
+
+        // Concept tasks may not have a deadline time set
+        this.subtask.deadline = this.subtask.deadline
+          ? moment(this.subtask.deadline).format('YYYY-MM-DD HH:mm:SS')
+          : null;
 
         if (this.subtask?.id) {
           const timesheets = this.subtask.timesheets.map((timesheet) => {
@@ -920,6 +929,10 @@ export default {
     },
 
     _mergeDeadlineTimeDate() {
+      // Override for concept tasks which may not have a deadline time set (check for invalid date)
+      if (isNaN(new Date(this.subtask.deadline).getTime())) {
+        this.subtask.deadline = null;
+      } else {
         const date = new Date(this.subtask.deadline);
         const timeParts = this.subtask._deadline_time.split(':');
 
@@ -927,6 +940,7 @@ export default {
         date.setMinutes(parseInt(timeParts[1]));
 
         this.subtask.deadline = date;
+      }
     },
 
     _validateEmployees() {