Websocket transport option in MQTT client

**Describe the problem you have/What new integration you would like**

I've created the cloudflare tunnel for my local mqtt broker, so I can access it from internet. Unfortunately it works only through websocket transport. Can the MQTT client configuration be extendend with websocket transport option?

**Please describe your use case for this integration and alternatives you've tried:**

This will enable nicely the access to local mqtt broker from esphome devices running outside of local HA network (second flat, summer house etc).

**Additional context**

No files, tests, or implementation entry points are identified in the request. Start by locating the MQTT client configuration and existing transport handling, then determine the scope of adding websocket transport; done means ESPHome devices can connect to the described broker through the Cloudflare tunnel.

Written by the indexing model from the issue text.