Add native meta-framework support for client <-> server communication (SolidStart, SvelteKit, Nuxt, TanStack Start, Next.js, Astro, etc.)

[fabian-hiller]

This is planned for Formisch v2. We look for experts in all meta-frameworks who help us implement and validate it. Feel free to reach out here or join our Discord: https://discord.gg/tkMjQACf2P