Acceptance criteria:
- When evaluating a call from wikitext, don't error if the inputs aren't Z6s (remove existing code)
- Attempt to run the parser of the target type with the given input, and if successful pass on.
- Question: What language do we use as the context language for the parser? The content language of the wiki?
- If parsing fails (or there is no parser), show a MediaWiki-style error and don't try to evaluate.
- Add some parser tests demonstrating happy path (and maybe failure?).