Fix skill frontmatter validation

.skills/csharp-best-practices/SKILL.md

@@ -3,7 +3,6 @@ name: csharp-best-practices
 description: >
   C# 14 / .NET 10 coding conventions, idiomatic patterns, and performance best practices
   for the Minecraft Console Client codebase. Use when writing, reviewing, or modifying C# code.
-version: 0.4.0
 ---
 
 # C# 14 / .NET 10 Best Practices

.skills/csharp-dotnet-cli-optimization/SKILL.md

@@ -31,7 +31,6 @@ metadata:
     - slow
     - hang
     - deadlock
-version: 0.2.0
 ---
 
 # C#/.NET CLI Optimization

.skills/csharp-optimization/SKILL.md

@@ -7,7 +7,6 @@ metadata:
   category: technique
   triggers: performance, allocations, GC, hot path, latency, throughput,
     memory pressure, optimize, slow, freeze, lag spike, packet processing speed
-version: 0.2.0
 ---
 
 # C# Performance Optimization for MCC

.skills/humanizer/SKILL.md

@@ -1,6 +1,5 @@
 ---
 name: humanizer
-version: 2.1.1
 description: |
   Remove signs of AI-generated writing from text. Use when editing or reviewing
   text to make it sound more natural and human-written. Based on Wikipedia's

.skills/writing-skills/SKILL.md

@@ -1,10 +1,6 @@
 ---
 name: writing-skills
 description: "Use when creating, updating, or improving agent skills."
-category: meta
-risk: unknown
-source: community
-date_added: "2026-02-27"
 ---
 
 # Writing Skills (Excellence)