Repair generated docs links before validation

[chubes4]

Summary

• Wire the Docs Agent workflow wrapper to use the reusable docs-agent link repair helper before final link validation.
• Pass the checked-out docs-agent path into the runner so bootstrap outputs can be mechanically cleaned before validation.

Testing

• bash -n tests/playground-ci/scripts/run-docs-agent.sh
• php -l tests/playground-ci/scripts/validate-docs-links.php

AI assistance

• AI assistance: Yes
• Tool(s): OpenCode (GPT-5.5)
• Used for: Drafted the workflow wrapper changes and validation handoff for human review.