Add Krusty AI coding assistant agent extension

[BurgessTG]

Summary

This PR adds Krusty, a terminal-based AI coding assistant, as an agent server extension for Zed.

About Krusty

• Multi-provider AI support (Anthropic Claude, OpenRouter, OpenCodeZen, and more)
• 100+ language servers via Zed's WASM extension ecosystem
• Rich tool system for file operations, bash execution, web search, and code exploration
• Sessions and conversation persistence
• Full ACP (Agent Client Protocol) implementation

Extension Details

• ID: krusty
• Version: 0.2.0
• Repository: https://github.com/BurgessTG/Krusty
• Extension Repo: https://github.com/BurgessTG/krusty-zed-extension

Platforms Supported

• macOS (ARM64, x86_64)
• Linux (ARM64, x86_64)
• Windows (x86_64)

Checklist

• Extension repository is public
• LICENSE file included (MIT)
• Using HTTPS URL for submodule
• extension.toml follows schema_version 1
• SVG icon included (16x16)

[cla-bot]

We require contributors to sign our Contributor License Agreement, and we don't have @BurgessTG on file. You can sign our CLA at https://zed.dev/cla. Once you've signed, post a comment here that says '@cla-bot check'.

[cla-bot]

We require contributors to sign our Contributor License Agreement, and we don't have @BurgessTG on file. You can sign our CLA at https://zed.dev/cla. Once you've signed, post a comment here that says '@cla-bot check'.