Add media kit and update README

- Add dstack logo and branding assets in docs/assets/Dstack Logo Kit/
- Include horizontal, vertical, and icon versions in primary and dark themes
- Update README with Media Kit section and table of contents
- Provide high-resolution PNG and SVG formats for digital and print use

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: shelvenzhou

README.md

@@ -53,6 +53,7 @@ dstack is community driven. Open sourced and built by [Kevin Wang](https://githu
   - [Zero Trust HTTPS](#zero-trust-https)
   - [Certificate Transparency Log Monitor](#certificate-transparency-log-monitor)
 - [Troubleshooting](#-troubleshooting)
+- [Media Kit](#-media-kit)
 - [License](#-license)
 
 ---
@@ -456,6 +457,18 @@ Then try building again. For more information about this restriction, see the [U
 
 ---
 
+## 🎨 Media Kit
+
+The dstack logo and branding assets are available in the [media kit](./docs/assets/Dstack%20Logo%20Kit/):
+
+- **Horizontal logos**: Primary and dark versions in PNG/SVG formats
+- **Vertical logos**: Primary and dark versions in PNG/SVG formats  
+- **Icons**: Primary and dark versions in PNG/SVG formats
+
+All assets are provided in high-resolution formats suitable for both digital and print use.
+
+---
+
 ## 📄 License
 
 ```