fix packaging and imports and introduce tests with pytest.

still issues with celery worker.

application/parser/schema/base.py

@@ -2,7 +2,7 @@
 from dataclasses import dataclass
 
 from langchain.docstore.document import Document as LCDocument
-from parser.schema.schema import BaseDocument
+from application.parser.schema.schema import BaseDocument
 
 
 @dataclass