feat: add PDF and DOCX support to read_file using get-md

[akramcodez]

Description

This PR upgrades @nanocollective/get-md to the latest version and extends the read_file tool to support PDF and DOCX files by automatically converting them to Markdown. It also adds comprehensive test coverage to verify document conversion, backward compatibility for text files, and graceful handling of conversion failures.

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update

Testing

Automated Tests

• New features include passing tests in .spec.ts/tsx files
• All existing tests pass (pnpm test:all completes successfully)
• Tests cover both success and error scenarios

Manual Testing

• Tested with Ollama
• Tested with OpenRouter
• Tested with OpenAI-compatible API
• Tested MCP integration (if applicable)

Checklist

• Code follows project style guidelines
• Self-review completed
• Documentation updated (if needed)
• No breaking changes (or clearly documented)
• Appropriate logging added using structured logging (see [CONTRIBUTING.md](../CONTRIBUTING.md#logging))

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.