ci: add HOL skill-publish validate workflow

[internet-dot]

I opened this as a small validate-only check for the skill metadata in the repo.

A couple of repo-specific details I checked first:

• Open-source AI agent for web automation and scraping
• Browser Agent: The executor that directly interacts with web pages. It performs actions like clicking, typing, navigating, and extracting information using browser automation tools
• Critique Agent: The quality controller that analyzes actions, verifies results, and guides the workflow. It determines if tasks are complete or need refinement

This adds one workflow for . and leaves the runtime code alone.
It only runs the schema and trust checks for the skill metadata in validate mode.

If you would rather place the workflow under a different filename or point it at a different skill directory, I can adjust the branch.