Download history refactor pt3 (#706)

- Added canonical per-user visibility of requests and downloads via new
activity view table. Users get fully independent activity and history
views, while admins still see all.
- Replaces janky frontend + backend combination

tests/core/test_queue.py

@@ -0,0 +1,53 @@
+"""Tests for queue hook failure handling."""
+
+from unittest.mock import patch
+
+from shelfmark.core.models import DownloadTask
+from shelfmark.core.queue import BookQueue
+
+
+def _make_task(task_id: str = "task-1") -> DownloadTask:
+    return DownloadTask(
+        task_id=task_id,
+        source="direct_download",
+        title="Example Title",
+        user_id=1,
+        username="alice",
+    )
+
+
+def test_add_logs_queue_hook_failures():
+    queue = BookQueue()
+
+    def broken_hook(task_id: str, task: DownloadTask) -> None:
+        raise RuntimeError("boom")
+
+    queue.set_queue_hook(broken_hook)
+
+    with patch("shelfmark.core.queue.logger.warning") as mock_warning:
+        assert queue.add(_make_task()) is True
+
+    mock_warning.assert_called_once()
+    args = mock_warning.call_args.args
+    assert args[0] == "Queue hook failed while adding task %s: %s"
+    assert args[1] == "task-1"
+    assert str(args[2]) == "boom"
+
+
+def test_enqueue_existing_logs_queue_hook_failures():
+    queue = BookQueue()
+    assert queue.add(_make_task("task-2")) is True
+
+    def broken_hook(task_id: str, task: DownloadTask) -> None:
+        raise RuntimeError("boom")
+
+    queue.set_queue_hook(broken_hook)
+
+    with patch("shelfmark.core.queue.logger.warning") as mock_warning:
+        assert queue.enqueue_existing("task-2") is True
+
+    mock_warning.assert_called_once()
+    args = mock_warning.call_args.args
+    assert args[0] == "Queue hook failed while requeueing task %s: %s"
+    assert args[1] == "task-2"
+    assert str(args[2]) == "boom"