fix: plug all gaps found in deep review of indexing pipeline

surfsense_backend/tests/unit/indexing_pipeline/conftest.py

@@ -0,0 +1,15 @@
+import pytest
+
+
+@pytest.fixture
+def patched_chunker_instance(mocker):
+    mock = mocker.patch("app.indexing_pipeline.document_chunker.config.chunker_instance")
+    mock.chunk.return_value = [mocker.Mock(text="prose chunk")]
+    return mock
+
+
+@pytest.fixture
+def patched_code_chunker_instance(mocker):
+    mock = mocker.patch("app.indexing_pipeline.document_chunker.config.code_chunker_instance")
+    mock.chunk.return_value = [mocker.Mock(text="code chunk")]
+    return mock