Serve Plant-It via Tailscale sidecar

[kommandantredundant]

I cannot make Plant-It work properly serving it using a tailscale sidecar. Has anyone achieved this?
I can access the frontend but I cannot successfully serve the backend as they use different ports. I suppose I am running into the same problems as in #151

This is my serve.json, that works for all my other services:

{
    "TCP": {
      "443": {
        "HTTPS": true
      }
    },
    "Web": {
      "${TS_CERT_DOMAIN}:443": {
        "Handlers": {
          "/": {
            "Proxy": "http://plants:3000"
          }
        }
      }
    }
  }

Do I just have to add the backend here? How? Has anyone achieved this?

Thanks for helping out!