chore: regenerate spec/SKILL.md with quoted description

Apply the YAML-quoting generator fix to spec/SKILL.md, which arrived
via garrytan#1740 merge with an unquoted description that would have re-broken
Codex skill loading.

Why: jbetala7 flagged in garrytan#1739 review that garrytan#1740 would land first
without touching scripts/gen-skill-docs.ts, reintroducing the bug.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: GilbertzzzZZ

spec/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: spec
 version: 0.1.0
-description: Turn vague intent into a precise, executable spec in five phases. (gstack)
+description: "Turn vague intent into a precise, executable spec in five phases. (gstack)"
 allowed-tools:
   - Bash
   - Read