fix(skills): add missing YAML frontmatter to 7 skills

Codex CLI requires YAML frontmatter (---) in SKILL.md files.
6 skills were missing frontmatter entirely; laravel-verification had
a bare colon in its description causing an invalid YAML parse error.

skills/benchmark/SKILL.md

@@ -1,3 +1,9 @@
+---
+name: benchmark
+description: Use this skill to measure performance baselines, detect regressions before/after PRs, and compare stack alternatives.
+origin: ECC
+---
+
 # Benchmark — Performance Baseline & Regression Detection
 
 ## When to Use