Implement code changes to enhance functionality and improve performance

[gafda]

This pull request is a fix to the issue on Issue langchain-ai/langchain-community#187, and includes updates to the PDF parsing logic and dependency management, as well as minor configuration changes. The most important changes involve improving error handling and refining the extract_images_from_page method, adding new PDF-related dependencies, and simplifying configuration settings in pyproject.toml.

PDF Parsing Improvements:

• libs/community/langchain_community/document_loaders/parsers/pdf.py: Enhanced the extract_images_from_page method to handle cases where /Resources might be missing in the page object and added error handling to log warnings when image extraction fails. [1] [2]

Dependency Management:

• libs/community/pyproject.toml: Added new dependencies (pdfminer-six, pdfplumber, pymupdf, pypdf, and unstructured) under a new [pdf] section to support PDF-related functionality.

Configuration Simplification:

• libs/community/pyproject.toml: Updated mypy configuration values to use lowercase true for better consistency and readability.

[gafda]

Any news about my PR?