Hint on `Type` for type of type (e.g. 'typescript', 'flow')

[bennypowers]

coptic: Any interest in improving the controls? For example, size here has three options, so a radio is a little nicer than having to type in something IMO. If there’s 3+ it could default to a select maybe?

bennyp: This could maybe be automated from the type field in a custom elements manifest, however, we'd have to assume the type text is typescript in order to parse the union, where the manifest scema makes no such assumption

coptic: Ya that’s what I was playing around with. That’s a good point though not assuming TS. FWIW, stencils doc schema and generator is nice in that it does parse any union into a values array.

tl;dr: tools can't know for certain what kind of string the type text is. If we added a hint (per file, or per type), they could parse the type to do things like generate radio buttons for demos

per type:

{
  "schemaVersion": "1.0.0",
  "readme": "",
  "modules": [
    {
      "kind": "javascript-module",
      "path": "my-element.js",
      "declarations": [
        {
          "kind": "class",
          "name": "MyElement",
          "members": [
            {
              "kind": "field",
              "name": "type",
              "type": {
                "text": "'number'|'string'|'boolean'",
                "kind": "typescript"
              }
            }
          ]
        }
      ]
    }
  ]
}

per file

{
  "schemaVersion": "1.0.0",
  "readme": "",
  "modules": [
    {
      "kind": "javascript-module",
      "path": "my-element.js",
      "types": "typescript",
      "declarations": [
        {
          "kind": "class",
          "name": "MyElement",
          "members": [
            {
              "kind": "field",
              "name": "type",
              "type": {
                "text": "'number'|'string'|'boolean'",
              }
            }
          ]
        }
      ]
    }
  ]
}

[jogibear9988]

I think #51 means nearly the same