fix(repository): match v2 baseline filter source in _handlers

The cherry-picked _handlers.py imported filter classes directly from
the local _filters fallback to avoid self-triggering the deprecation
warning. But v2 baseline behavior was to prefer advanced_alchemy.filters
classes (with _filters as the AA-not-installed fallback). The change
broke test_app_repository_signature_namespace which asserts the
signature_namespace_values dict contains advanced_alchemy.filters
classes.

Restore the try/except pattern from upstream/v2:litestar/repository/
filters.py to keep the public class identity stable while still
avoiding the deprecation warning trigger inside the internal handler.

Author: cofin

litestar/repository/_handlers.py

@@ -1,16 +1,29 @@
 from typing import TYPE_CHECKING
 
-from litestar.repository._filters import (
-    BeforeAfter,
-    CollectionFilter,
-    FilterTypes,
-    LimitOffset,
-    NotInCollectionFilter,
-    NotInSearchFilter,
-    OnBeforeAfter,
-    OrderBy,
-    SearchFilter,
-)
+try:
+    from advanced_alchemy.filters import (
+        BeforeAfter,
+        CollectionFilter,
+        FilterTypes,
+        LimitOffset,
+        NotInCollectionFilter,
+        NotInSearchFilter,
+        OnBeforeAfter,
+        OrderBy,
+        SearchFilter,
+    )
+except ImportError:  # pragma: no cover
+    from litestar.repository._filters import (  # type: ignore[assignment]
+        BeforeAfter,
+        CollectionFilter,
+        FilterTypes,
+        LimitOffset,
+        NotInCollectionFilter,
+        NotInSearchFilter,
+        OnBeforeAfter,
+        OrderBy,
+        SearchFilter,
+    )
 
 if TYPE_CHECKING:
     from litestar.config.app import AppConfig