[skill-gap]: no new commands after install

### Affected skill

other / not sure

### Relevant instruction or excerpt

I installed all skills with command `npx skills add addyosmani/agent-skills`.

### Project context

I'm using github copilot in vscode.

### What did not work or did not apply

I can't find any commands in my agent, such as: `/spec`, `/plan`, `/build`, `/test`.

### What you did instead

_No response_

Reproduce by running `npx skills add addyosmani/agent-skills` and checking what command definitions are loaded into the agent. Start at the CLI/install entry path and the skill registration/loading logic to verify why the expected slash commands are missing. Run the project’s relevant smoke checks for command availability in a Copilot-in-VS Code context, and mark done when the installed skill exposes `/spec`, `/plan`, `/build`, and `/test`.

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