Generate component summary pages

[adam-collins]

For ease of manual validation against the pattern library

• Add functionality to produce a single page (html?) with all components, additional parameters and alternate variants listed and demonstrated.
• One page for each light/dark and desktop/mobile versions.
• Include anything else that might be useful for this manual validation step, e.g. colours.
• The order of components should align with the order they appear in the pattern library, and be searchable (Ctrl+F).
• May or may not need separate pages for complex components, e.g. header and footer.
• This doubles as documentation and should be built into /docs or equivalent.