fix: Apply subtask filtering to saved filters to prevent duplication

The bug was in ProjectList.vue where subtask filtering was skipped for saved
filters (projectId < 0). This caused subtasks to appear twice:
1. As standalone tasks in the main list
2. Nested under their parent tasks

The fix removes the early return for saved filters, ensuring the
shouldShowTaskInListView filter is always applied.

Co-authored-by: kolaente <13721712+kolaente@users.noreply.github.com>

frontend/src/components/project/views/ProjectList.vue

@@ -163,9 +163,8 @@ watch(
 	allTasks,
 	() => {
 		tasks.value = [...allTasks.value]
-		if (projectId.value < 0) {
-			return
-		}
+		// Filter out subtasks that have parents in the current view to avoid duplication
+		// This applies to all views including saved filters
 		tasks.value = tasks.value.filter(t => shouldShowTaskInListView(t, allTasks.value))
 	},
 )