SvelteKit 3 Hits Release Candidate

The Svelte team has moved SvelteKit 3 into release candidate phase, with a stable release expected if testing goes smoothly. Configuration moves from svelte.config.js to vite.config.ts, the $lib alias is retired for #lib, and Svelte 5 and Vite 8 with Rolldown are now required. Error handling and service worker modules also change.