fix trailing slash issue

- see SvelteKit bug: sveltejs/kit#11317
- downgrading to @sveltejs/kit@1.30.0 until we're ready for 2.x
- fixes #681

package.json

@@ -24,7 +24,7 @@
     "@csstools/postcss-global-data": "^2.1.0",
     "@playwright/test": "^1.37.1",
     "@sveltejs/adapter-node": "^1.3.1",
-    "@sveltejs/kit": "^1.30.3",
+    "@sveltejs/kit": "1.30.0",
     "@testing-library/jest-dom": "^6.1.2",
     "@testing-library/svelte": "^4.0.3",
     "@testing-library/user-event": "^14.4.3",