feat: implement 'not_started' task status with validation and UI updates

src/lib/queries/tasks.js

@@ -90,7 +90,7 @@ export function createProjectTask(data) {
 		result = stmt.run(
 			data.project_id,
 			data.task_template_id,
-			data.status || "pending",
+			data.status || "not_started",
 			data.priority || "normal",
 			data.created_by || null,
 			data.assigned_to || null
@@ -114,7 +114,7 @@ export function createProjectTask(data) {
 			data.custom_task_name,
 			data.custom_max_wait_days || 0,
 			data.custom_description || "",
-			data.status || "pending",
+			data.status || "not_started",
 			data.priority || "normal",
 			data.created_by || null,
 			data.assigned_to || null