Merge origin/main; resolve Docker file conflicts

PR #1 was squash-merged to main with the initial Dockerfile/README.
Keep the Compose-enhanced versions from this branch (superset).

README.md

@@ -86,6 +86,7 @@ GitHub Actions runs lint, typecheck, and tests on every pull request and push to
 
 ## Docker
 
+<<<<<<< HEAD
 ### docker compose (recommended)
 
 ```bash
@@ -116,16 +117,26 @@ docker compose down
 
 ### Plain docker
 
+=======
+>>>>>>> origin/main
 ```bash
 docker build -t rfid-database .
 docker run --rm -p 3000:3000 \
   -e AUTH_SECRET=your-long-secret \
+<<<<<<< HEAD
   -e CREATE_USER_EMAIL=[email protected] \
   -e CREATE_USER_PASSWORD=changeme \
+=======
+>>>>>>> origin/main
   -v rfid-data:/data \
   rfid-database
 ```
 
+<<<<<<< HEAD
+=======
+Create the first user against the mounted DB (exec into the container or run `create-user` with `RFID_DB_PATH` pointed at the volume).
+
+>>>>>>> origin/main
 ## Security
 
 Tag dumps often include sector keys. Keep the app behind HTTPS, do not expose it publicly without auth, and treat `data/rfid.db` as sensitive.