feat: initial scaffold of CrowdSec admin webapp

Flask + htmx mini-app to list and delete CrowdSec decisions from a browser,
gated behind Authentik. Talks to host LAPI via host.docker.internal:8080
using machine JWT auth (bouncer X-Api-Key is read-only).

Gitea Actions CI/CD on push to main: runner rebuilds image and brings the
stack up via docker compose on the host (same pattern as flight-radar).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/Dockerfile

@@ -0,0 +1,14 @@
+FROM python:3.12-slim
+
+WORKDIR /app
+
+COPY requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+
+COPY app.py .
+COPY templates/ templates/
+
+ENV PYTHONUNBUFFERED=1
+EXPOSE 8000
+
+CMD ["gunicorn", "-b", "0.0.0.0:8000", "-w", "2", "--access-logfile", "-", "app:app"]