Add `enabled` field to library.yaml entries

[nikhilmaddirala]

Problem

Currently, all entries (skills, agents, prompts) defined in library.yaml are always enabled. There's no built-in way to conditionally enable or disable specific entries when using the library in different contexts (e.g., different machines, projects, or use cases).

Proposed Solution

Add an optional enabled boolean field to each entry in the library (skills, agents, prompts). When not specified, it should default to true (backward compatible).

Example

Current structure:

library:
  skills:
    - name: my-skill
      description: What this skill does
      source: /Users/me/projects/tools/skills/my-skill/SKILL.md
      requires: [agent:helper-agent]

Desired structure:

library:
  skills:
    - name: my-skill
      description: What this skill does
      source: /Users/me/projects/tools/skills/my-skill/SKILL.md
      requires: [agent:helper-agent]
      enabled: true

Benefits

• Enable/disable entries per environment or context without deleting them
• Easily toggle entries on/off during development
• Keep a single source of truth for definitions
• Maintain backward compatibility (default to true)

[pascalandy]

I like that. My duct tape solution at the moment is to have another directory called : skill_archived