chore: make whoosh imports lazy to unblock test collection during Tantivy migration

Module-level whoosh imports in tasks.py and paperless/views.py prevented
test collection after removing whoosh-reloaded. Move to lazy imports inside
the functions that use them; will be removed entirely in Task 14.

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

src/documents/tasks.py

@@ -20,9 +20,7 @@ from django.db import transaction
 from django.db.models.signals import post_save
 from django.utils import timezone
 from filelock import FileLock
-from whoosh.writing import AsyncWriter
 
-from documents import index
 from documents import sanity_checker
 from documents.barcodes import BarcodePlugin
 from documents.bulk_download import ArchiveOnlyStrategy
@@ -84,12 +82,20 @@ def _identity(iterable: Iterable[_T]) -> Iterable[_T]:
 
 @shared_task
 def index_optimize() -> None:
+    from whoosh.writing import AsyncWriter
+
+    from documents import index
+
     ix = index.open_index()
     writer = AsyncWriter(ix)
     writer.commit(optimize=True)
 
 
 def index_reindex(*, iter_wrapper: IterWrapper[Document] = _identity) -> None:
+    from whoosh.writing import AsyncWriter
+
+    from documents import index
+
     documents = Document.objects.all()
 
     ix = index.open_index(recreate=True)
@@ -270,6 +276,10 @@ def sanity_check(*, scheduled=True, raise_on_error=True):
 
 @shared_task
 def bulk_update_documents(document_ids) -> None:
+    from whoosh.writing import AsyncWriter
+
+    from documents import index
+
     documents = Document.objects.filter(id__in=document_ids)
 
     ix = index.open_index()
@@ -300,6 +310,8 @@ def update_document_content_maybe_archive_file(document_id) -> None:
     Re-creates OCR content and thumbnail for a document, and archive file if
     it exists.
     """
+    from documents import index
+
     document = Document.objects.get(id=document_id)
 
     mime_type = document.mime_type

src/paperless/views.py

@@ -35,7 +35,6 @@ from rest_framework.permissions import IsAuthenticated
 from rest_framework.response import Response
 from rest_framework.viewsets import ModelViewSet
 
-from documents.index import DelayedQuery
 from documents.permissions import PaperlessObjectPermissions
 from documents.tasks import llmindex_index
 from paperless.filters import GroupFilterSet
@@ -72,6 +71,8 @@ class StandardPagination(PageNumberPagination):
         )
 
     def get_all_result_ids(self):
+        from documents.index import DelayedQuery  # removed with Whoosh in Task 14
+
         query = self.page.paginator.object_list
         if isinstance(query, DelayedQuery):
             try: