Augment vue instead of @vue/runtime-core

See documentation for augmenting global properties: https://vuejs.org/guide/typescript/options-api.html#augmenting-global-properties

Legacy @vue/runtime-core breaks with vue-router@^4.4.1

Cf: vuejs/language-tools#4793 (comment)

types/vue.d.ts

@@ -10,7 +10,7 @@ declare module "vue/types/vue" {
   }
 }
 
-declare module '@vue/runtime-core' {
+declare module 'vue' {
   interface ComponentCustomProperties {
     $cookies: VueCookies
   }