Update install-activate-setup-theme

[bph]

Use the InstallTheme > themeData option
and resource=git:directory.
current step:

{
	"step": "installTheme",
	"themeZipFile": {
		"resource": "url",
		"url": "https://github-proxy.com/proxy/?repo=richtabor/kanso&branch=main"
	},
	"options": {
		"activate": true
	}
},

The new step:

{
  "step": "installTheme",
  "themeData": {
    "resource": "git:directory",
    "repositoryUrl": "https://github.com/richtabor/kanso",
    "ref": "main",
    "path": "/"
  },
  "options": {
    "activate": true
  }
}

[bph]

The correct InstallTheme step

{
	"step": "installTheme",
		"themeData": {
			"resource":"url",
			  "url": "https://github.com/richtabor/kanso/archive/refs/heads/main.zip"
			},
			"options": {
			  "activate": true
			}
},