fix: 修正不显示讨论区仍然禁用某些快捷键的问题

src/store/modules/pdf.js

@@ -13,7 +13,7 @@ export default {
     slideInfo: {},
     totalPages: 0,
     currentPage: 1,
-    showDiscussion: false,
+    showDiscussion: true,
     focus: false
   },
 

src/views/reader/PdfReader.vue

@@ -59,7 +59,7 @@ export default {
         this.focus && this.$store.commit(USE_FOCUS)
         return
       }
-      if (!this.focus) {
+      if (!this.showDiscussion || !this.focus) {
         switch (e.key) {
           case 'ArrowDown':
           case 'ArrowRight':