It sounds like you have a misunderstanding about SvelteKit. It does have a client side router and you can use SvelteKit as a pure SPA today very easily, all you need is to set `export const ssr = false;` and `export const prerender = false;` in `src/routes/+layout.ts`. Then export with `adapter-static` and you're done.
Swing by the official Svelte Discord, we're happy to discuss your questions! https://discord.com/invite/svelte