build(deps): upgrade web to SvelteKit 3 and vitest 5

Move the SvelteKit config into vite.config.js, replace the $lib alias with
#lib subpath imports (dropping the vitest alias), extend $app/tsconfig, and
pass asset() paths without a leading slash. Drop the @babel/core and js-yaml
overrides, which no longer match anything in the tree.

web/jsconfig.json

@@ -1,9 +1,9 @@
 {
-  "extends": "./.svelte-kit/tsconfig.json",
+  "extends": "$app/tsconfig",
   "compilerOptions": {
-    "allowJs": true,
-    "checkJs": false,
-    "module": "esnext",
-    "moduleResolution": "bundler"
-  }
+    "checkJs": false
+  },
+  "include": [
+    "src"
+  ]
 }