feat: add kanban board

src/kanban/buildKanbanBoard.ts

@@ -0,0 +1,33 @@
+import { Task, TaskStatus } from "@/model/task";
+import { TASK_STATUS_LABELS, TASK_STATUS_ORDER } from "@/ui/taskLabels";
+
+export type KanbanColumn = {
+	status: TaskStatus;
+	label: string;
+	tasks: Task[];
+};
+
+export type KanbanBoard = {
+	columns: KanbanColumn[];
+};
+
+/** Build fixed-order status columns; empty columns are kept (unlike groupTasks). */
+export function buildKanbanBoard(tasks: Task[]): KanbanBoard {
+	const columns: KanbanColumn[] = TASK_STATUS_ORDER.map((status) => {
+		const columnTasks = tasks
+			.filter((task) => task.status === status)
+			.slice()
+			.sort(
+				(a, b) =>
+					new Date(b.updated).getTime() - new Date(a.updated).getTime(),
+			);
+
+		return {
+			status,
+			label: TASK_STATUS_LABELS[status],
+			tasks: columnTasks,
+		};
+	});
+
+	return { columns };
+}