Social demo

The social feed that used to be on dihlabs.lol, now its own app: a token panel, compose box, feed and post pages as optz islands, over the Rust engine in portfolio/engine (the $12 Server Challenge entry) mounted at /api/social.

# the engine (see portfolio/engine/README.md for a seed database)
cd portfolio/engine && SQLITE_PATH=/tmp/feed.db JWT_SECRET=dev HOST=127.0.0.1 PORT=3000 bash start.sh
# the app
cd apps/social && bun run dev        # http://127.0.0.1:3005
sudo python3 ops/mint-token.py NAME  # on the server: a token to post and like with

ENGINE_URL points it at another engine.