[FEATURE] Add skills metadata to /context command summary

[PaulRBerg]

Problem

The /context command provides a helpful breakdown of context window usage, but it currently omits skills metadata from the summary. The command shows:

• System prompt
• System tools
• MCP Tools
• Custom agents
• Memory files
• Messages
• Free Space

However, skills (SKILL.md files) also consume context tokens since their name and description metadata are loaded at startup. Users have no visibility into how much context their installed skills are using.

Proposed solution

Add a "Skills" category to the /context command output that shows:

• Number of skills loaded
• Approximate tokens consumed by skill metadata (names + descriptions)

Example output:

Skills:          12 skills (~1,200 tokens)

Alternatives considered

None - this seems like a straightforward addition to the existing context summary.

Priority

Medium

Category

CLI commands and flags

Related issue: #14834

[PaulRBerg]

Based on what Claude told me (see below), the skills' metadata is part of System tools.

They definitely deserve their bespoke category, though.

Skills metadata is included in System tools.
Specifically, the Skill tool definition contains an <available_skills> block listing all skills with their:

• Name
• Description (trigger phrases)
• Location (user, project, managed, plugin)