Initial commit: MKV → AVI web app (Docker + Keycloak OIDC)

- App FastAPI : recherche dans un dossier média, download original ou
  conversion en AVI Xvid (tone-mapping HDR→SDR, audio FR auto, MP3 stéréo)
- Auth Keycloak OIDC (Authlib) optionnelle
- 3 composes : app seule, stack local (keycloak.local), production (NPM)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Dockerfile

@@ -0,0 +1,22 @@
+# ffmpeg/ffprobe statiques complets (incluent zscale/zimg pour le tone-mapping HDR)
+FROM mwader/static-ffmpeg:7.1 AS ffmpeg
+
+FROM python:3.12-slim
+COPY --from=ffmpeg /ffmpeg /usr/local/bin/ffmpeg
+COPY --from=ffmpeg /ffprobe /usr/local/bin/ffprobe
+
+WORKDIR /app
+COPY requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+COPY app/ /app/
+
+ENV MEDIA_DIR=/media \
+    OUTPUT_DIR=/output \
+    MAX_WORKERS=1
+
+EXPOSE 8000
+VOLUME ["/media", "/output"]
+
+# --proxy-headers : respecte X-Forwarded-Proto/Host derrière Nginx Proxy Manager
+CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000", \
+     "--proxy-headers", "--forwarded-allow-ips", "*"]