[Feature] Plugin system for custom tools and commands

[DaveSimoes]

🧩 Plugin System for Custom Tools and Commands

This is a roadmap feature open for community contribution!

🎯 Overview

We want CrustAI to support a plugin architecture so developers can
add custom commands and tool integrations without modifying the core codebase.

💡 Vision

// Example: a user-created plugin
export default {
  name: 'weather',
  command: '/weather',
  description: 'Get current weather for a city',
  async handle({ args, reply }) {
    const data = await fetchWeather(args[0]);
    reply(`🌤️ ${data.city}: ${data.temp}°C`);
  }
};

Users drop this file into a plugins/ folder and CrustAI auto-loads it.

🏗️ What needs to be built

• Plugin loader in src/core/ that scans a plugins/ directory on startup
• Plugin interface/contract (what methods a plugin must export)
• Command registry that maps /command → plugin handler
• 2 example plugins to document the pattern:
  • /weather — simple HTTP fetch
  • /remind — scheduled message reminder
• Documentation in docs/ for plugin authors

✅ Acceptance Criteria

• Plugins loaded dynamically at startup with no core code changes
• Broken plugins fail gracefully with a warning (no crash)
• Works across all adapters (Telegram, Discord, WhatsApp, Slack)
• CONTRIBUTING.md updated with plugin development guide

📐 Architecture discussion

Before coding, let's align on the plugin interface.
Please share your design proposal in the comments!

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🚀 This is a high-impact architectural feature. Ideal for experienced JS devs
who want to leave a lasting mark on the project. We'll credit you prominently in the README!