docs: add SpecKit Companion to Community Friends section (#2140)

Add SpecKit Companion VS Code extension to the Community Friends
listing alongside existing community projects.

Author: alfredoperez

README.md

@@ -286,6 +286,8 @@ Community projects that extend, visualize, or build on Spec Kit:
 
 - **[Spec Kit Assistant](https://marketplace.visualstudio.com/items?itemName=rfsales.speckit-assistant)** — A VS Code extension that provides a visual orchestrator for the full SDD workflow (constitution → specification → planning → tasks → implementation) with phase status visualization, an interactive task checklist, DAG visualization, and support for Claude, Gemini, GitHub Copilot, and OpenAI backends. Requires the `specify` CLI in your PATH.
 
+- **[SpecKit Companion](https://marketplace.visualstudio.com/items?itemName=alfredoperez.speckit-companion)** — A VS Code extension that brings a visual GUI to Spec Kit. Browse specs in a rich markdown viewer with clickable file references, create specifications with image attachments, comment and refine each step inline (GitHub-style review), track your progress through the SDD workflow with a visual phase stepper, and manage steering documents like constitutions and templates.
+
 ## 🤖 Supported AI Agents
 
 | Agent                                                                                | Support | Notes                                                                                                                                     |