feat: add share message as image functionality (#553)

* feat: add share message as image functionality

- Add html-to-image dependency for DOM-to-PNG conversion
- Add share button to agent message footer with loading state
- Generate high-quality PNG images with 24px padding for better readability
- Use theme-aware background colors
- Handle errors gracefully with toast notifications

* fix: align lockfile workspace versions to 1.8.1

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Co-authored-by: Jovines <jovines@qq.com>
Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>

packages/ui/package.json

@@ -64,6 +64,7 @@
     "fuse.js": "^7.1.0",
     "ghostty-web": "^0.4.0",
     "heic2any": "^0.0.4",
+    "html-to-image": "^1.11.13",
     "http-proxy-middleware": "^3.0.5",
     "motion": "^12.23.24",
     "next-themes": "^0.4.6",