fix: siteTitle vs pageTitle

Author: yyx990803

lib/app/dataMixin.js

@@ -46,9 +46,12 @@ export default {
       }
       return targetLang || defaultLang || {}
     },
+    $siteTitle () {
+      return this.$localeConfig.title || this.$site.title || ''
+    },
     $title () {
       const page = this.$page
-      const siteTitle = this.$localeConfig.title || this.$site.title || ''
+      const siteTitle = this.$siteTitle
       const selfTitle = page.frontmatter.home ? null : (
         page.frontmatter.title || // explicit title
         page.title // inferred title

lib/default-theme/Navbar.vue

@@ -6,9 +6,9 @@
         v-if="$site.themeConfig.logo"
         :src="$withBase($site.themeConfig.logo)">
       <span class="site-name"
-        v-if="$title"
+        v-if="$siteTitle"
         :class="{ 'can-hide': $site.themeConfig.logo }">
-        {{ $title }}
+        {{ $siteTitle }}
       </span>
     </router-link>
     <div class="links">