SvelteKit configuration in svelte.config.js: adapter, alias, appDir, csp (mode/directives/reportOnly), csrf (checkOrigin/trustedOrigins), embedded, env (dir/publicPrefix/privatePrefix), experimental (tracing/instrumentation/remoteFunctions), inlineStyleThreshold, moduleExtensions, outDir, output (preloadStrategy/bundleStrategy), paths (assets/base/relative), prerender (concurrency/crawl/entries/error handlers/origin), router (type/resolution), typescript (config function), version (name/pollInterval).