Accessibility settings to the app

Screen reader readable "Show Help" button.
Also added a new checkbox for accessibility settings.

src/lang/cn.ts

@@ -19,6 +19,7 @@ export const languageChinese = {
         onlyOneChat: '必须至少有一次聊天',
         alreadyCharInGroup: "群组中已存在同名的角色。"
     },
+    showHelp: "显示帮助",
     help:{
         model: "模型选项是用于聊天的主要模型。",
         submodel: "辅助模型是用于分析情绪图像，自动建议等的模型。推荐使用gpt3.5。",

src/lang/en.ts

@@ -19,6 +19,7 @@ export const languageEnglish = {
         onlyOneChat: 'There must be least one chat',
         alreadyCharInGroup: "There is already a character with the same name in the group."
     },
+    showHelp: "Show Help",
     help:{
         model: "Model option is a main model used in chat.",
         submodel: "Auxiliary Model is a model that used in analizing emotion images and auto suggestions and etc. gpt3.5 is recommended.",

src/lang/ko.ts

@@ -149,6 +149,7 @@ export const languageKorean = {
     ShowLog: "리퀘스트 로그 보기",
     waifuWidth2: "Waifu 캐릭터 크기",
     sayNothing:"어떤 문자열도 입력되지 않을 시 'say nothing' 입력",
+    showHelp: "도움말 보기",
     help:{
         model: "채팅에서 사용되는 모델입니다.",
         submodel: "보조 모델은 감정 이미지, 자동 제안등을 분석하는 데 사용되는 모델입니다. gpt3.5가 권장됩니다.",