Fix migration check in deploy script to use reliable exit code (#267)

`docker compose wait migrate | grep -qx "0"` was unreliable because
`docker compose wait` output format may not match the literal string "0".

Replace with `docker compose up --no-deps migrate` (foreground, no -d),
which exits with the container's actual exit code — no grep needed.

https://claude.ai/code/session_01WRe4qZuV2NQqDYurpDodF4

Co-authored-by: Claude <noreply@anthropic.com>

.github/workflows/deploy.yml

@@ -149,8 +149,7 @@ jobs:
                       docker login $CONTAINER_REGISTRY -u $REGISTRY_USERNAME -p $REGISTRY_PASSWORD
                       cd brackt
                       docker compose pull
-                      docker compose up -d migrate
-                      if ! docker compose wait migrate | grep -qx "0"; then
+                      if ! docker compose up --no-deps migrate; then
                         echo "Migration failed:"
                         docker compose logs migrate
                         exit 1