+ add docling to init import

Author: choinek

text_extract_api/files/file_formats/__init__.py

@@ -4,5 +4,6 @@
 ###    Run ./scripts/dev/gen-file-format-init.sh from repository root.
 
 from .file_format import FileFormat
+from .docling import DoclingFileFormat
 from .pdf import PdfFileFormat
 from .image import ImageFileFormat