Support parameterized skills

[agzam]

I have a skill that I'd like to use with arguments, e.g.

  /review-pr URL

And it seems ECA right now doesn't support that. Even when the skill has $ARGUMENTS in the .md file, ECA does it in two steps. It loads the skill and says: "I'm ready to use it, give me a URL or a ref number". Alternatively, I could just use natural language "review this PR URL" and hope ECA picks up the right skill from the conversational context. Neither is ideal.

It would be great if ECA supported passing arguments to skills.