chore: add CODEOWNERS (#121)

## Summary
- Adds `.github/CODEOWNERS` routing all paths to the infra owners from
`godaddy/cli`'s fallback line, plus `dclayton-godaddy`.

## Test plan
- N/A — reviewer routing metadata only.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

Author: jpage-godaddy

.github/CODEOWNERS

@@ -0,0 +1,3 @@
+# Reviewer routing for godaddy/cli-engine.
+
+* @axburgess-godaddy @dclayton-godaddy @jpage-godaddy @jpearlman-godaddy @mguerrero3-godaddy @qcai-godaddy @rts1-godaddy @runruh-godaddy