fix: escape @ symbol in i18n strings

Author: lyingbug

frontend/src/i18n/locales/en-US.ts

@@ -328,7 +328,7 @@ export default {
       noKnowledgeBaseDesc: 'Pure model conversation, no knowledge retrieval',
       selectKnowledgeBases: 'Select Knowledge Bases',
       retrieveKBOnlyWhenMentioned: 'Retrieve Only When Mentioned',
-      retrieveKBOnlyWhenMentionedDesc: 'Off: auto-retrieve configured KBs; On: retrieve only when user @ mentions',
+      retrieveKBOnlyWhenMentionedDesc: "Off: auto-retrieve configured KBs; On: retrieve only when user {'@'} mentions",
       rerankModel: 'ReRank Model',
       rerankModelDesc: 'Used to rerank knowledge base retrieval results for better accuracy',
       rerankModelPlaceholder: 'Select ReRank Model',

frontend/src/i18n/locales/zh-CN.ts

@@ -857,8 +857,8 @@ export default {
       noKnowledgeBase: "不使用知识库",
       noKnowledgeBaseDesc: "纯模型对话，不检索知识库",
       selectKnowledgeBases: "选择知识库",
-      retrieveKBOnlyWhenMentioned: "仅在 @ 提及时检索",
-      retrieveKBOnlyWhenMentionedDesc: "关闭：自动检索已配置的知识库；开启：仅当用户 @ 提及时才检索",
+      retrieveKBOnlyWhenMentioned: "仅在 {'@'} 提及时检索",
+      retrieveKBOnlyWhenMentionedDesc: "关闭：自动检索已配置的知识库，开启：仅当用户 {'@'} 提及时才检索",
       rerankModel: "ReRank 模型",
       rerankModelDesc: "用于对知识库检索结果进行重排序，提高回答准确性",
       rerankModelPlaceholder: "请选择 ReRank 模型",