Refresh the stale specs glob example in .2119.yml

[tylerwillis]

Context: #10 broadened the default spec glob to specs/**/*.md, while this repository's commented example in .2119.yml still shows specs/**/*REQ-*.md.

Source: deferred item in the final dual-review triage: #10 (comment)

Why deferred: The stale line is a non-functional comment and did not affect the feature's behavior or gates.

Implementation outline:

• Refresh the generated configuration comment to match the current default.
• Update the source template if needed so future initialization produces the correct example.
• Add or adjust snapshot/assertion coverage for generated configuration text.