Skills: use installed ghcrawl binary in protocol docs

[huntharo]

Summary

Update the ghcrawl skill protocol and skill docs to prefer the installed ghcrawl binary instead of repo-local pnpm --filter ghcrawl cli ... commands.

Why

The skill protocol still reflects the earlier in-repo development workflow, not the current operator workflow where ghcrawl is installed on the system and should be invoked directly.

That mismatch creates avoidable failures and confusion:

• the skill tells agents to run pnpm --filter ghcrawl cli ...
• the current intended operator surface is ghcrawl ...
• repo-maintainer/dev commands and installed-user commands are getting mixed together in the skill’s default source of truth

Current State

Concrete references:

• skills/ghcrawl/SKILL.md
  • still includes pnpm --filter ghcrawl cli ... examples
• skills/ghcrawl/references/protocol.md
  • currently documents the command protocol with pnpm --filter ghcrawl cli doctor --json
  • and the rest of the protocol examples also use the repo-local pnpm form

These files are supposed to be the default source of truth for the ghcrawl skill, so they should match the real installed command surface.

Desired Behavior

• The ghcrawl skill should default to direct ghcrawl command examples in its protocol and usage guidance.
• Repo-maintainer/development-only commands can still live in maintainer docs, but they should not be the primary protocol examples for the skill.
• The protocol should be explicit about when to use:
  • installed binary form: ghcrawl ...
  • repo-dev form: only when actively working on ghcrawl itself

Acceptance Criteria

• skills/ghcrawl/references/protocol.md uses ghcrawl ... as the default command form.
• skills/ghcrawl/SKILL.md no longer leads the agent toward pnpm --filter ghcrawl cli ... for normal usage.
• Any remaining repo-dev pnpm examples are clearly marked as maintainer-only.
• The updated protocol matches the actual installed CLI behavior.

Notes

• Keep this issue scoped to the skill protocol/docs, not broader CLI packaging changes.
• This is a fast board-shrinking cleanup with direct operator impact.