feat(observability): add structured application logging

Emit correlated JSON logs from the API and FunASR services, propagate request IDs to the client, and configure bounded opt-in Docker logging.

Document the host-wide Grafana/Loki query workflow and keep observability deployment ownership outside the application repository.

pages/profile/index.wxss

@@ -70,6 +70,10 @@
   font-size: 25rpx;
 }
 
+.request-id-row {
+  margin-left: 28rpx;
+}
+
 .check-button {
   margin-top: 24rpx;
 }