Implement an example of weaver generate registry subcommand

[lquerel]

The weaver generate registry subcommand must demonstrate one of the following capabilities:

• Generate HTML documentation for a registry (weaver generate registry doc-html).
• Generate code for a registry in a specific language (weaver generate registry go-semconv).
• Generate a dashboard configuration for elements defined in a semconv registry.
• Or any other useful subcommand to demonstrate the generate registry command.

The main goal is to create a framework for generating various outputs from a resolved semconv registry.