feat: Enhance Marketplace and Skill Management UI with improved error handling and user feedback

- Updated MarketplaceDrawer to include security notes and manual installation hints.
- Refactored SkillDetailDrawer to display default icons for skills.
- Simplified SkillListItem to use default icons for better readability.
- Integrated gateway status checks and warnings in SkillsPage for improved user awareness.
- Enhanced error handling for skill installation and fetching, providing clearer feedback to users.
- Added new translations for error messages and gateway warnings to improve localization support.

package.json

@@ -6,13 +6,16 @@
   "main": "dist-electron/main/main.js",
   "scripts": {
     "init": "pnpm install && pnpm run uv:download",
+    "predev": "zx scripts/prepare-preinstalled-skills-dev.mjs",
+    "prestart": "zx scripts/prepare-preinstalled-skills-dev.mjs",
     "dev": "vite",
     "start": "vite",
-    "build": "vite build && electron-builder",
+    "build": "vite build && zx scripts/bundle-preinstalled-skills.mjs && electron-builder",
     "build:vite": "vite build",
     "test": "vitest run",
     "smoke:agents": "node scripts/agents-runtime-smoke.mjs",
-    "package": "vite build",
+    "bundle:preinstalled-skills": "zx scripts/bundle-preinstalled-skills.mjs",
+    "package": "vite build && zx scripts/bundle-preinstalled-skills.mjs",
     "icons": "zx scripts/generate-icons.mjs",
     "uv:download": "zx scripts/download-bundled-uv.mjs",
     "uv:download:mac": "zx scripts/download-bundled-uv.mjs --platform=mac",