[FEATURE] Wrap or truncate slash command descriptions in autocomplete dropdown

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When typing a slash command (e.g. /dash), the autocomplete dropdown shows skill names and their descriptions on a single line. Many skill descriptions are 100-500+ characters long, which causes them to extend far beyond the visible terminal width.

On a standard 2560px wide monitor, descriptions are truncated with "..." but the truncation point is so far to the right that the text still extends well past the screen edge. With many installed skills (100+), the autocomplete dropdown becomes unusable because you can't read the descriptions to distinguish between similar commands.

This is especially problematic when skill names are similar (e.g. multiple interface-design variants, multiple asc-* commands) and the description is the only way to tell them apart.

Proposed Solution

Option A (preferred): Wrap skill descriptions to a second line in the autocomplete dropdown, with the description indented under the command name. This preserves the full description while keeping it readable.

Option B: Truncate descriptions at a reasonable column width (e.g. 80-100 characters from the start of the description text, not from the left edge of the terminal). The current truncation appears to use the full terminal width, which on wide monitors means descriptions can be 200+ visible characters before truncation kicks in.

Option C: Allow a max-description-length config option in settings.json so users can control the truncation point.

Any of these would make the autocomplete usable for users with many skills installed.

Alternative Solutions

Current workaround is manually editing each skill file to shorten the description field in YAML frontmatter. This is tedious with 100+ skills and doesn't solve the underlying UI issue -- new skills from the marketplace will still have long descriptions.

Priority

Medium - Would be very helpful

Feature Category

Interactive mode (TUI)

Use Case Example

1. I have 100+ skills installed from the marketplace for experimenting across projects
2. 2. I type /dash to find dashboard-related skills
3. 3. The autocomplete shows 6 matches, but descriptions extend far past screen edge
4. 4. I cannot read descriptions to tell /metrics-dashboard from /interface-design variants
5. 5. With wrapped descriptions, I could quickly scan and pick the right skill

Additional Context

_No response_