fix(auth): login 500 — DataProtection key ring on root-owned volume (#37)

docker-compose.yml

@@ -53,6 +53,16 @@ services:
       postgres:
         condition: service_healthy
 
+  # One-shot: ensure the DataProtection 'keys' volume is owned by the API's non-root
+  # 'app' user (uid 1654). A volume created by an older root-running image is root-owned,
+  # which makes the app fail to read its key ring and 500s on login. Runs as root, chowns,
+  # exits; the api waits for it. Idempotent and cheap.
+  init-keys:
+    image: busybox
+    command: ["sh", "-c", "chown -R 1654:1654 /keys"]
+    volumes:
+      - keys:/keys
+
   api:
     build:
       context: .
@@ -79,6 +89,8 @@ services:
     depends_on:
       postgres:
         condition: service_healthy
+      init-keys:
+        condition: service_completed_successfully
     # V-08: bind to loopback so the API is not directly reachable from the network
     # (only via the frontend/nginx proxy over the internal compose network). This
     # prevents external clients from bypassing the proxy to spoof X-Forwarded-* headers.