- Add client-side code runner via Web Workers (PicoC for C, MicroPython WASM for Python)
- Support interactive stdin with SharedArrayBuffer and Atomics
- Implement offline database mirror using Dexie.js with opportunistic auto-sync
- Add execution mode toggle in Playground (Browser vs Server)
- Configure COOP, COEP, and CORP security headers in SvelteKit server hook
- Fix Velxio and Flowchart Nginx headers and add credentialless attribute to iframes
- Mount Nginx configs in podman-compose.yml for velxio and flowchart services
- Add unit and E2E Playwright integration tests (100% passed)
- Update lesson_service.py to parse markdown link format [title](path)
- Convert all lesson files to use markdown link format for prerequisites
- Backend now extracts slug directly from link path
- Supports both plain text and markdown link formats
a2nr