Implement personal section in navigation: Add a new 'personal' menu item with sub-items for language learning and calendar. Update localization files for English and German to include translations for the new section. Integrate personal routes into the router configuration for navigation.

frontend/src/i18n/locales/de/navigation.json

@@ -7,6 +7,7 @@
         "chats": "Chats",
         "falukant": "Falukant",
         "minigames": "Minispiele",
+        "personal": "Persönliches",
         "settings": "Einstellungen",
         "administration": "Verwaltung",
         "m-chats": {
@@ -41,6 +42,17 @@
             "match3": "Match 3 - Juwelen",
             "taxi": "Taxi Simulator"
         },
+        "m-personal": {
+            "sprachenlernen": "Sprachen lernen",
+            "calendar": "Kalender",
+            "m-sprachenlernen": {
+                "vocabtrainer": "Vokabeltrainer",
+                "sprachkurse": "Sprachkurse",
+                "m-vocabtrainer": {
+                    "newLanguage": "Neue Sprache"
+                }
+            }
+        },
         "m-settings": {
             "homepage": "Startseite",
             "account": "Account",