perf(dashboard): slim task list + auto-archive stale done tasks

GET /api/tasks was returning ~69 MB of JSON per call (67.9 MB of agent
logs across 1199 tasks), causing the dashboard to hang for 2+ minutes.

- core: extend listTasks() with slim and includeArchived options
- dashboard: GET /api/tasks now uses slim mode and excludes archived
  by default; ?includeArchived=1 opts in
- frontend: lazy-load archived tasks when the archived column is first
  expanded via new useTasks.loadArchivedTasks()
- engine: self-healing maintenance now auto-archives done tasks older
  than 48h (data stays in SQLite, column flips done -> archived)
- tests: slim mode + includeArchived coverage in store.test.ts;
  routes.test.ts assertion updated for new args

Also bundles in-progress test-setup noise filters and pre-existing
QuickEntryBox/routes test work that was already modified locally.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/core/src/store.test.ts

@@ -1322,6 +1322,42 @@ describe("TaskStore", () => {
       expect(paged).toHaveLength(1);
       expect(paged[0].id).toBe("FN-002");
     });
+
+    it("slim mode returns metadata but drops heavy fields (log/comments/steps)", async () => {
+      const task = await store.createTask({ description: "Slim test" });
+      await store.logEntry(task.id, "heavy log entry that should not appear in slim list");
+
+      const fullList = await store.listTasks();
+      const slimList = await store.listTasks({ slim: true });
+
+      const full = fullList.find((t) => t.id === task.id)!;
+      const slim = slimList.find((t) => t.id === task.id)!;
+
+      expect(full.log.length).toBeGreaterThan(0);
+      expect(slim.id).toBe(task.id);
+      expect(slim.description).toBe("Slim test");
+      expect(slim.column).toBe(full.column);
+      expect(slim.log).toEqual([]);
+      expect(slim.steps).toEqual([]);
+      expect(slim.comments).toBeUndefined();
+    });
+
+    it("includeArchived=false excludes archived tasks; default includes them", async () => {
+      const keep = await store.createTask({ description: "Stays visible" });
+      const toArchive = await store.createTask({ description: "Will be archived" });
+      await store.moveTask(toArchive.id, "todo");
+      await store.moveTask(toArchive.id, "in-progress");
+      await store.moveTask(toArchive.id, "in-review");
+      await store.moveTask(toArchive.id, "done");
+      await store.archiveTask(toArchive.id);
+
+      const withArchived = await store.listTasks();
+      const withoutArchived = await store.listTasks({ includeArchived: false });
+
+      expect(withArchived.map((t) => t.id)).toEqual(expect.arrayContaining([keep.id, toArchive.id]));
+      expect(withoutArchived.map((t) => t.id)).toContain(keep.id);
+      expect(withoutArchived.map((t) => t.id)).not.toContain(toArchive.id);
+    });
   });
 
   describe("SQLite-first reads when task blobs are missing", () => {