Support namespaced element types in WOD files

[hugithordarson]

Currently WOD declarations don't support namespaced element types. Since inline syntax supports namespaces (<html:div>, <wo:String>), WOD files should too for feature completeness.

Proposed syntax

Use dot as the namespace separator in the type position:

Banner : html.div {
    class = "container";
}

Greeting : wo.String {
    value = name;
}

The dot avoids ambiguity with the existing colon separator between declaration name and type (MyTag : Type).

Priority

Low — WOD files are legacy syntax and existing WOD declarations don't use namespaces. This is a nice-to-have for completeness rather than a pressing need.