feat: add PDF hydration and R2 upload scripts - Updated package.json to include new scripts for hydrating PDFs and uploading to R2. - Created r2-pdf-worker.js for serving PDFs from Cloudflare R2. - Added wrangler.toml.example for Cloudflare R2 configuration. - Implemented resolvePdfUrl function to construct PDF URLs. - Added example environment profile for R2 configuration. - Created hydrate-pdfs.mjs script to download and hydrate PDF files. - Developed upload-r2-pdfs.mjs script for uploading PDFs to R2. - Added PowerShell script to load R2 profile environment variables.