feat: Propagate SVG changes in customCollections to client and server bundles without nuxt server restart

[leo-buneev]

🔗 Linked issue

resolves #281

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

watches changes in files from customCollections directories, and on any change triggers:

• rebuild of client icons bundle
• rebuild of server icons bundle
• invalidates client bundle in vite dev server

Potential future improvements (let me know if you're interested, i can create further PR):

• debounce bundles rebuilding in case of rapid file changes
• HMR - probably needs custom message from HMR server to Icon.vue