chore: temporarily derive Beszel public key

compose.yaml

@@ -19,3 +19,15 @@ services:
       timeout: 5s
       start_period: 15s
       retries: 3
+
+  beszel-key-helper:
+    image: alpine:3.22
+    container_name: beszel-key-helper
+    restart: "no"
+    volumes:
+      - /app-config/beszel/hub:/hub:ro
+      - /app-config/beszel/key-helper:/out
+    command: >-
+      sh -c "apk add --no-cache openssh-client >/dev/null &&
+      ssh-keygen -y -f /hub/id_ed25519 > /out/id_ed25519.pub &&
+      sleep 600"