Add reedsolo to Docker, update docs for docker/ paths

- Add reedsolo>=1.7.0 to Dockerfile and Dockerfile.base for DCT
  error correction (fixes DCT decode failures in container)
- Update all documentation to use docker/docker-compose.yml paths

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docker/Dockerfile.base

@@ -32,7 +32,8 @@ RUN pip install --no-cache-dir \
     jpegio>=0.2.0 \
     argon2-cffi>=23.0.0 \
     pillow>=10.0.0 \
-    cryptography>=41.0.0
+    cryptography>=41.0.0 \
+    reedsolo>=1.7.0
 
 # Install web/api framework packages (also stable)
 RUN pip install --no-cache-dir \