Make it possible to change port of ESPHome dashboard

[DutchmanNL]

currently option is blocked in adapter instance configuration, waiting for fix of command line port setting : https://github.com/esphome/issues/issues/2078

[kubax]

i second that!

i have a docker server with multiple containers, all reachable by FQDN on port 80 / 443 (80 just redirecting to 443) the ESPhome IS reachable through the FQDN and 443, and through the normal dns name of the machine + the port, but havin everything behind a official certificate, the browser stops from loading the iframe of the esphome on the default port, becaus it just uses http.

Edit: it may even be a value that is only changable in advanced mode...

Edit2: i hacked in the port into the json config file for iobroker. could you also add an option to switch the url from http to https? because it still tries to load over http://host:443 wich naturally failed.