feat(document-search): determine document type automatically

[mhordynski]

Feature description

DocumentSearch should be capable to automatically determine document type based on the provided file.

This may be implemented with allowing additional type Source in async def ingest_document(self, document: Union[DocumentMeta, Document], document_processor: Optional[BaseProvider] = None) -> None: method inside DocumentSearch - then fetching source and determining document type

Motivation

Right now the main entrypoint to document ingestion pipeline requires DocumentMeta instance, which has required field document_type. It forces users to either know document type beforhand, or to detect it outsite of ragbits.

Additional context

No response