Add keyboard handling in VocabPracticeDialog for improved user interaction

- Implemented keydown event listener to manage Enter key functionality for navigating questions and submitting answers.
- Enhanced user experience by allowing Enter to trigger actions based on the current dialog state, improving accessibility during practice sessions.
- Ensured proper cleanup of event listeners when closing the dialog to prevent memory leaks.

frontend/src/dialogues/socialnetwork/VocabPracticeDialog.vue

@@ -185,6 +185,9 @@ export default {
       this.locked = false;
       this.resetQuestion();
       this.$refs.dialog.open();
+      this.$nextTick(() => {
+        document.addEventListener('keydown', this.handleKeyDown);
+      });
       this.reloadPool();
     },
     close() {
@@ -194,11 +197,32 @@ export default {
       }
       const cb = this.onClose;
       this.onClose = null;
+      document.removeEventListener('keydown', this.handleKeyDown);
       this.$refs.dialog.close();
       try {
         if (cb) cb();
       } catch (_) {}
     },
+    handleKeyDown(event) {
+      // Enter soll bei "Weiter" (falsch beantwortet) funktionieren.
+      // Im Tippmodus soll Enter weiterhin "Prüfen" auslösen (Input hat eigenen handler).
+      if (event.key !== 'Enter' && event.keyCode !== 13) return;
+
+      if (this.showNextButton) {
+        event.preventDefault();
+        this.next();
+        return;
+      }
+
+      // Falls man im Tippmodus ist und der Fokus NICHT im Input liegt, erlauben wir Enter als "Prüfen".
+      if (!this.answered && !this.simpleMode && !this.locked) {
+        const tag = event.target?.tagName?.toLowerCase?.();
+        if (tag !== 'input' && tag !== 'textarea') {
+          event.preventDefault();
+          this.submitTyped();
+        }
+      }
+    },
     normalize(s) {
       return String(s || '')
         .trim()