fix(*): align remaining types and publish runtime follow-up

[Rishabh060105]

Follow-up to #669

This PR is a focused follow-up on top of #669 to address the remaining gaps found during review.

Changes

• Updated .github/workflows/publish.yml to use Node 22 so the release workflow matches the new engines.node >=22 requirement introduced in feat: tighten TypeScript type declarations — replace any with concrete types #669
• Tightened the remaining weak public types by updating HtmlTransformer to emit HtmlInput / IDocument and TemplateMarkTransformer.getSerializer() to emit Serializer

Flags

• This PR is intentionally based on feat/tighten-typescript-types so the diff stays limited to the follow-up fixes instead of duplicating feat: tighten TypeScript type declarations — replace any with concrete types #669
• packages/markdown-template still has the existing no-console lint warnings in its source, but this follow-up does not introduce any new lint errors

Screenshots or Video

• Not applicable

Related Issues

• Issue feat: tighten TypeScript type declarations — replace any with Concerto model types #668
• Pull Request feat: tighten TypeScript type declarations — replace any with concrete types #669

Author Checklist

• Ensure you provide a DCO sign-off for your commits using the --signoff option of git commit.
• Vital features and changes captured in unit and/or integration tests
• Commits messages follow AP format
• Extend the documentation, if necessary
• Merging to feat/tighten-typescript-types from Rishabh060105/pr669-followup-fixes

Validation

• npm run build --workspace packages/markdown-template
• npm run build --workspace packages/markdown-html
• npm run lint --workspace packages/markdown-template
• npm run lint --workspace packages/markdown-html
• npm test --workspace packages/markdown-template
• npm test --workspace packages/markdown-html