feat: add backup monitoring database schema

backend/tests/test_backups.py

@@ -0,0 +1,16 @@
+import tempfile
+from pathlib import Path
+from media_library_viewer_api.services.settings_store import SettingsStore
+
+
+def test_backup_schema_created():
+    with tempfile.TemporaryDirectory() as tmpdir:
+        db_path = Path(tmpdir) / "test_settings.sqlite"
+        store = SettingsStore(db_path)
+        store.init_schema()
+        with store.connect() as conn:
+            tables = conn.execute("SELECT name FROM sqlite_master WHERE type='table' AND name LIKE 'backup_%'").fetchall()
+            table_names = [t[0] for t in tables]
+            assert "backup_jobs" in table_names
+            assert "backup_runs" in table_names
+            assert "backup_alerts" in table_names