Refactor module template

**Describe your use case**
The module template code is out of date and doesn't illustrate the full set of concepts. We can refactor this template and its inclusion in documentation.

**Describe alternatives solutions you've considered**
To be discussed.

**Additional context**
None

The issue identifies the module template and its inclusion in documentation, but names no files, tests, or entry points. Start by locating the template and the documentation section that includes it, then clarify which concepts the updated example must cover before making changes. Done means the template is current and the documentation presents it consistently.

Written by the indexing model from the issue text.