Fix PDF worker in bundled environments (Next.js, webpack)

Fix CJS path resolution: use __filename fallback for pnpm strict layout

Fix PDF converter CJS compatibility: use createRequire fallback for path resolution

Fix XLSX converter inflating output 15x via merged cell duplication

Remove prepare script to prevent recursive pnpm install in Docker

chore: include dist in repo for reliable GitHub installs

fix: handle invalid Date values in XLSX cell formatting

fix: add prepare script and missing devDeps for GitHub install builds

test: add tests for markitdown() convenience function, FileType enum, and Axios support

fix: handle Axios string responses and add clear error for unsupported data types

feat: add FileType enum, auto-detection from magic bytes, and Axios support

feat: flatten markitdown() options -- filename, mimetype, charset are top-level

feat: add markitdown() convenience function and rewrite README

docs: add Vercel Blob usage example to README

docs: add README with usage examples, API reference, and security docs