Remove the separate docx-to-pdf upload API and integrate DOCX conversion directly into the blob upload finalize route. Update client and uploader logic to treat DOCX as a supported upload type and streamline batch state handling. Adjust document caching and test helpers to align with the new unified flow. Add server-side DOCX-to-PDF conversion utility and corresponding unit tests.
This change simplifies the upload pipeline, consolidates conversion logic, and improves maintainability.
