deploy: add 110 proxysql host canary entrypoint

ops/110-proxysql/20-production-entrypoint.yaml

@@ -0,0 +1,18 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: mysql-prd
+  namespace: prd
+  labels:
+    app.kubernetes.io/name: proxysql
+    app.kubernetes.io/part-of: mes-prd-database
+spec:
+  externalIPs:
+    - 192.168.110.208
+  selector:
+    app: proxysql-prd
+  ports:
+    - name: mysql-legacy-14006
+      port: 14006
+      targetPort: mysql
+      protocol: TCP

ops/110-proxysql/README.md

@@ -37,7 +37,11 @@ kubectl apply -f 00-host-mysql-entrypoints.yaml
 kubectl apply -f 10-proxysql.yaml
 ```
 
-Only `proxysql-prd-canary.prd.svc:3306` is created. Do not create or replace
-the production `mysql-prd` Service, change Rainbond environment variables, or
-retire MaxScale until canary routing has passed and a separate cutover is
-approved.
+Use `20-production-entrypoint.yaml` first with the temporary external port
+`192.168.110.208:14006`. After SQL routing passes, change that same Service to
+port `4006`, stop `maxscale-container`, and apply the pushed production
+revision. Existing clients keep their original `192.168.110.208:4006`
+configuration.
+
+Rollback uses the pushed `14006` revision to remove the Service's `4006`
+mapping, followed by `docker start maxscale-container`.