Implement Agent Skills plugin for BotSharp

[Copilot]

Adds a new plugin enabling AI agents to leverage reusable skills following the Agent Skills specification.

New Plugin: BotSharp.Plugin.AgentSkills

Core Components

• SkillLoader/SkillParser - Discovers and parses SKILL.md files with YAML frontmatter from user (~/.botsharp/skills/) and project-level directories
• SkillValidator - Validates skill names (lowercase alphanumeric + hyphens, max 64 chars), descriptions, and file sizes

Agent Functions

• skill-read_skill - Read full SKILL.md content for a skill
• skill-read_skill_file - Read files within a skill directory
• skill-list_skill_directory - List skill directory contents

Security

• Path traversal protection via ResolveSafePath
• Symlink validation for external targets
• File size limits (10 MB) and output truncation

Usage

Create skills in ~/.botsharp/skills/{skill-name}/SKILL.md:

---
name: web-research
description: Performs web research and summarizes findings
license: MIT
allowed-tools: http_* search_*
---

# Web Research Skill

Instructions for the agent...

Configure via AgentSkillsSettings:

{
  "AgentSkills": {
    "EnableUserSkills": true,
    "EnableProjectSkills": true,
    "SkillsCacheDurationSeconds": 300
  }
}

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• agentskills.io
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

参考 https://github.com/sheng-jie/Maf.AgentSkills 的代码为botsharp 实现Agent Skills

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[iceljc]

Better to remove any Chinese characters and use English only.