feat(api): Add mock API routes for testing GIS lines and station names

- Created mock API route for fetching GIS lines data (/api/talas_v5_DB/gisLines/readGisLinesMock)
- Created mock API route for fetching station names data (/api/talas_v5_DB/station/getAllStationsNamesMock)
- Replaced original API calls in useLineData hook with mock routes for development and testing

components/EditModeToggle.js

@@ -1,6 +1,7 @@
 import React, { useState, useEffect } from "react";
 import DesignServicesIcon from "@mui/icons-material/DesignServices";
 import EditOffIcon from "@mui/icons-material/EditOff";
+import ModeEditIcon from "@mui/icons-material/ModeEdit";
 import Tooltip from "@mui/material/Tooltip"; // Importiere Tooltip von Material-UI
 
 function EditModeToggle() {
@@ -27,7 +28,7 @@ function EditModeToggle() {
         </Tooltip>
       ) : (
         <Tooltip title="Bearbeitungsmodus aktivieren" placement="top">
-          <DesignServicesIcon />
+          <ModeEditIcon />
         </Tooltip>
       )}
     </div>