feat: option to hide title in case of logo

close https://github.com/vuejs/vitepress/issues/637

src/client/theme-default/components/VPNavBarTitle.vue

@@ -10,8 +10,10 @@ const { hasSidebar } = useSidebar()
   <div class="VPNavBarTitle" :class="{ 'has-sidebar': hasSidebar }">
     <a class="title" href="/">
       <img v-if="theme.logo" class="logo" :src="theme.logo" :alt="site.title">
-      {{ site.title }}
+      <template v-if="theme.siteTitle">{{ theme.siteTitle }}</template>
+      <template v-else-if="theme.siteTitle || !theme.logo">{{ site.title }}</template>
     </a>
+
   </div>
 </template>
 

types/default-theme.d.ts

@@ -7,6 +7,11 @@ export namespace DefaultTheme {
      */
     logo?: string
 
+    /**
+     * Custom site title in navbar
+     */
+    siteTitle?: string | false
+
     /**
      * The nav items.
      */