Ability to specify custom command

[solonovamax]

Hi,

sorry for the lack of use of the issue templates, I'm on mobile (FastHub) and it doesn't support them

I would like if I could specify a custom command instead of using ngrok.

for example, if I wanted to use my own self-hosted bore server, I could specify the command as

bore local {{port}} --to proxy.solonovamax.gay --secret $BORE_SECRET

where, {{port}} is the local port.
however, this presents the issue of knowing the port for the resulting url. so, instead it could be something like

bore local {{localPort}} --to proxy.solonovamax.gay --secret $BORE_SECRET --port {{remotePort}}

where localPort is the local port and remotePort is the remote port, chosen randomly.
and, the resulting url can be specified as

proxy.solonovamax.gay:{{remotePort}}

additionally, there can be settings for a maximum and minimum port, as services like bore only accept ports within a certain range.