"Tag name as style scope" rule

[jbmoelker]

Summary

Proposed changes:

• "Tag name as style scope" rule (incl. summary, why, how and examples).

  Checklist

• [X] The changes only affect or contain one style guide rule or section.
• [X] The changes are in style guide format.
• [X] The new style guide section has an entry in the Table of Contents (only if changes introduce new section).
• [X] The changes can be merged into the target branch without conflicts.