fix: add PUT /tasks/mirror (array full-replace of desktop Idle backlog)

The desktop pushes its full Idle backlog as a JSON array to /tasks/mirror, not per-task.
Previously /tasks/mirror matched tasks/[id].put.ts (id=mirror) and rejected the array with
400. New static route validates per-element, accepts empty arrays, upserts each as
consumed=true (desktop-owned), deletes consumed=true rows not in the array, and leaves
web-created consumed=false rows untouched. Mirrors PUT /lists.

tests/repo.test.ts

@@ -93,3 +93,66 @@ describe("tasks", () => {
     expect(await repo.getTasksForList(sql, "L")).toEqual([]);
   });
 });
+
+describe("mirrorDesktopTasks (desktop Idle full-replace)", () => {
+  beforeEach(async () => {
+    await repo.replaceLists(sql, [
+      { id: "L", name: "List" },
+      { id: "L2", name: "List 2" },
+    ]);
+  });
+
+  it("inserts items as desktop-owned (consumed=true, source=desktop)", async () => {
+    await repo.mirrorDesktopTasks(sql, [
+      { id: "m1", listId: "L", title: "one", description: "d1" },
+      { id: "m2", listId: "L2", title: "two" },
+    ]);
+    const t = await repo.getTasksForList(sql, "L");
+    expect(t).toHaveLength(1);
+    expect(t[0]).toMatchObject({ id: "m1", title: "one", description: "d1", source: "desktop", consumed: true });
+    expect(await repo.getTasksForList(sql, "L2")).toHaveLength(1);
+  });
+
+  it("upserts existing items by id (title/listId/description)", async () => {
+    await repo.mirrorDesktopTasks(sql, [{ id: "m1", listId: "L", title: "one" }]);
+    await repo.mirrorDesktopTasks(sql, [{ id: "m1", listId: "L2", title: "renamed", description: "x" }]);
+    const onL = await repo.getTasksForList(sql, "L");
+    const onL2 = await repo.getTasksForList(sql, "L2");
+    expect(onL).toHaveLength(0);
+    expect(onL2).toHaveLength(1);
+    expect(onL2[0]).toMatchObject({ title: "renamed", description: "x" });
+  });
+
+  it("deletes desktop tasks whose id is not in the array", async () => {
+    await repo.mirrorDesktopTasks(sql, [
+      { id: "m1", listId: "L", title: "one" },
+      { id: "m2", listId: "L", title: "two" },
+    ]);
+    await repo.mirrorDesktopTasks(sql, [{ id: "m1", listId: "L", title: "one" }]); // m2 dropped
+    const t = await repo.getTasksForList(sql, "L");
+    expect(t.map((x) => x.id)).toEqual(["m1"]);
+  });
+
+  it("empty array deletes all desktop tasks", async () => {
+    await repo.mirrorDesktopTasks(sql, [{ id: "m1", listId: "L", title: "one" }]);
+    await repo.mirrorDesktopTasks(sql, []);
+    expect(await repo.getTasksForList(sql, "L")).toEqual([]);
+  });
+
+  it("does NOT touch web-created tasks awaiting pull (consumed=false)", async () => {
+    const web = await repo.createWebTask(sql, { listId: "L", title: "web", description: null });
+    await repo.mirrorDesktopTasks(sql, [{ id: "m1", listId: "L", title: "desk" }]);
+    // web task survives the mirror (and is still unconsumed)
+    const unconsumed = await repo.getUnconsumed(sql);
+    expect(unconsumed.map((x) => x.id)).toEqual([web.id]);
+    expect((await repo.getTasksForList(sql, "L")).map((x) => x.id).sort()).toEqual([web.id, "m1"].sort());
+  });
+
+  it("claims a web task when its id is mirrored (becomes consumed=true)", async () => {
+    const web = await repo.createWebTask(sql, { listId: "L", title: "web", description: null });
+    await repo.mirrorDesktopTasks(sql, [{ id: web.id, listId: "L", title: "web (imported)" }]);
+    expect(await repo.getUnconsumed(sql)).toEqual([]); // no longer awaiting pull
+    const t = await repo.getTasksForList(sql, "L");
+    expect(t[0]).toMatchObject({ id: web.id, title: "web (imported)", consumed: true });
+  });
+});