fix: prevent duplicate series when same anime key exists in different folder

- Add check for existing series by key in SetupService.run to skip duplicates
- Fix Path construction in initialization_service.py cleanup function
- Update unit tests to mock get_by_key and get_series_app

tests/unit/test_setup_service.py

@@ -167,10 +167,16 @@ class TestSetupServiceRun:
         mock_get_db = MagicMock()
         mock_get_db.__aenter__.return_value = mock_db
         mock_get_db.__aexit__.return_value = None
+        mock_series_app = AsyncMock()
+        mock_series_app.search.return_value = []
 
         with patch(
             'src.server.services.setup_service.settings'
         ) as mock_settings, \
+             patch(
+                 'src.server.services.setup_service.get_series_app',
+                 return_value=mock_series_app
+             ), \
              patch(
                  'src.server.services.setup_service.get_db_session',
                  return_value=mock_get_db
@@ -179,6 +185,10 @@ class TestSetupServiceRun:
                  'src.server.services.setup_service.AnimeSeriesService.get_by_folder',
                  new_callable=AsyncMock, return_value=None
              ), \
+             patch(
+                 'src.server.services.setup_service.AnimeSeriesService.get_by_key',
+                 new_callable=AsyncMock, return_value=None
+             ), \
              patch(
                  'src.server.services.setup_service.UnresolvedFolderService.get_by_folder_name',
                  new_callable=AsyncMock, return_value=None
@@ -258,10 +268,16 @@ class TestSetupServiceRun:
         mock_get_db = MagicMock()
         mock_get_db.__aenter__.return_value = mock_db
         mock_get_db.__aexit__.return_value = None
+        mock_series_app = AsyncMock()
+        mock_series_app.search.return_value = []
 
         with patch(
             'src.server.services.setup_service.settings'
         ) as mock_settings, \
+             patch(
+                 'src.server.services.setup_service.get_series_app',
+                 return_value=mock_series_app
+             ), \
              patch(
                  'src.server.services.setup_service.get_db_session',
                  return_value=mock_get_db
@@ -270,6 +286,10 @@ class TestSetupServiceRun:
                  'src.server.services.setup_service.AnimeSeriesService.get_by_folder',
                  new_callable=AsyncMock, return_value=None
              ), \
+             patch(
+                 'src.server.services.setup_service.AnimeSeriesService.get_by_key',
+                 new_callable=AsyncMock, return_value=None
+             ), \
              patch(
                  'src.server.services.setup_service.UnresolvedFolderService.get_by_folder_name',
                  new_callable=AsyncMock, return_value=None
@@ -323,6 +343,10 @@ class TestSetupServiceRun:
                  'src.server.services.setup_service.AnimeSeriesService.get_by_folder',
                  new_callable=AsyncMock, return_value=None
              ), \
+             patch(
+                 'src.server.services.setup_service.AnimeSeriesService.get_by_key',
+                 new_callable=AsyncMock, return_value=None
+             ), \
              patch(
                  'src.server.services.setup_service.UnresolvedFolderService.get_by_folder_name',
                  new_callable=AsyncMock, return_value=None
@@ -401,6 +425,10 @@ class TestSetupServiceRun:
                  'src.server.services.setup_service.AnimeSeriesService.get_by_folder',
                  new_callable=AsyncMock, return_value=None
              ), \
+             patch(
+                 'src.server.services.setup_service.AnimeSeriesService.get_by_key',
+                 new_callable=AsyncMock, return_value=None
+             ), \
              patch(
                  'src.server.services.setup_service.UnresolvedFolderService.get_by_folder_name',
                  new_callable=AsyncMock, return_value=None