Add pl8list infinite-scroll app with pl8list sign-in

Endless TikTok-style feed over pl8list's Remix loaders. A guest crawler
builds a shared catalogue; a per-user ranker learns from likes, full
listens and skips. Users sign in with pl8list's email code; only a hash
of the local session token is stored. Ships as a hardened Docker image
with a Traefik override for pl8.narl.io.

Dockerfile

@@ -0,0 +1,22 @@
+# syntax=docker/dockerfile:1
+FROM python:3.14-alpine
+
+ENV PYTHONUNBUFFERED=1 \
+    PYTHONDONTWRITEBYTECODE=1 \
+    HOST=0.0.0.0 \
+    PORT=8790 \
+    PL8_DB=/data/pl8list.db
+
+WORKDIR /app
+COPY *.py ./
+COPY static ./static
+RUN python -m compileall -q . \
+ && adduser -D -H -u 10001 app \
+ && mkdir /data && chown app:app /data
+
+USER app
+VOLUME /data
+EXPOSE 8790
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s \
+  CMD python -c "import urllib.request; urllib.request.urlopen('http://127.0.0.1:8790/healthz', timeout=2)"
+CMD ["python", "server.py"]