Enhance PDF generation and update configurations: Add PDF_LOGO_PATH to .env.example, include markdown-pdf in requirements.txt, and refactor PDF generation logic to support logo integration. Introduce tests for PDF generation from Markdown input and update summarizer agent to streamline export functionality.

Enhance conversation workflows by introducing summarization and classification agents. Implement retrieval nodes for document fetching, and update settings for Supabase integration. Add Markdown to PDF conversion utilities and improve agent service to handle document metadata. Refactor agent registry to support orchestrated workflows.