feat: JWT-Authentifizierung in SettingModal implementiert und Modal-Stabilität verbessert

- JWT-Token-Erstellung und -Speicherung für sichere Admin-Authentifizierung in SettingModal hinzugefügt.
- Stabilitätsprobleme des Modals behoben.
- Funktionalität des Modals und des Tokens überprüft, um eine reibungslose Benutzererfahrung sicherzustellen.

package-lock.json

@@ -26,6 +26,7 @@
         "react-modal": "^3.16.1",
         "react-redux": "^9.1.2",
         "react-spinners": "^0.14.1",
+        "react-toastify": "^10.0.6",
         "redux": "^5.0.1",
         "redux-persist": "^6.0.0"
       },
@@ -662,6 +663,14 @@
       "resolved": "https://registry.npmjs.org/client-only/-/client-only-0.0.1.tgz",
       "integrity": "sha512-IV3Ou0jSMzZrd3pZ48nLkT9DA7Ag1pnPzaiQhpW7c3RbcqqzvzzVu+L8gfqMp/8IM2MQtSiqaCxrrcfu8I8rMA=="
     },
+    "node_modules/clsx": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/clsx/-/clsx-2.1.1.tgz",
+      "integrity": "sha512-eYm0QWBtUrBWZWG0d386OGAw16Z995PiOVo2B7bjWSbHedGl5e0ZWaq65kOGgUSNesEIDkB9ISbTg/JK9dhCZA==",
+      "engines": {
+        "node": ">=6"
+      }
+    },
     "node_modules/color-convert": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/color-convert/-/color-convert-2.0.1.tgz",
@@ -1688,6 +1697,18 @@
         "react-dom": "^16.0.0 || ^17.0.0 || ^18.0.0"
       }
     },
+    "node_modules/react-toastify": {
+      "version": "10.0.6",
+      "resolved": "https://registry.npmjs.org/react-toastify/-/react-toastify-10.0.6.tgz",
+      "integrity": "sha512-yYjp+omCDf9lhZcrZHKbSq7YMuK0zcYkDFTzfRFgTXkTFHZ1ToxwAonzA4JI5CxA91JpjFLmwEsZEgfYfOqI1A==",
+      "dependencies": {
+        "clsx": "^2.1.0"
+      },
+      "peerDependencies": {
+        "react": ">=18",
+        "react-dom": ">=18"
+      }
+    },
     "node_modules/read-cache": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/read-cache/-/read-cache-1.0.0.tgz",