Rename the step decorator in showcase_repl_actor_run_steps.py from
'the JSON should be valid' to 'the examples JSON content is valid'
to avoid collision with the identical step already defined in
aimodelsproviders_steps.py (which uses a different context variable).
Update the matching step text in showcase_repl_actor_run.feature.
ISSUES CLOSED: #7552
- Register REPL and actor run showcase in examples.json
- Add BDD tests for showcase documentation structure
- Verify markdown file exists and is properly formatted
- Validate JSON metadata for showcase entry
- Test documented commands and content sections
Closes#7552