Merge branch 'dev' into 'main'

chat auswahl deaktivierbar

See merge request kantz/tutor_react!7

math-tutor/frontend/.env-example

 VITE_FRONTEND_LANG="de"
+VITE_SHOW_CHATS_BUTTON="true"

math-tutor/frontend/src/pages/ChatPage.tsx

@@ -91,6 +91,11 @@ const toRetrievedDoc = (source: ContextSource, index: number): RetrievedDoc => (
 });
 
 export default function ChatPage() {
+  const showChatsButton = String(
+    import.meta.env.VITE_SHOW_CHATS_BUTTON ?? "true"
+  )
+    .trim()
+    .toLowerCase() !== "false";
   const navigate = useNavigate();
   const {
     chatSessionId,
@@ -649,6 +654,7 @@ export default function ChatPage() {
   return (
     <div className="app-shell">
       <header className="app-header">
+        {showChatsButton ? (
           <button
             type="button"
             className="btn sidebar-toggle"
@@ -656,6 +662,7 @@ export default function ChatPage() {
           >
             {t("chats")}
           </button>
+        ) : null}
         <div className="brand">
           <span className="brand-mark">SUM</span>
           <div className="brand-text">