feat: unifica lo smistamento CAD su destinazione unica configurabile da UI

preload.js

@@ -3,5 +3,7 @@ const { contextBridge, ipcRenderer } = require('electron');
 contextBridge.exposeInMainWorld('api', {
   selectFolder: () => ipcRenderer.invoke('select-folder'),
   selectZip: () => ipcRenderer.invoke('select-zip'),
-  getConfigPath: () => ipcRenderer.invoke('get-config-path'),
+  getDestination: () => ipcRenderer.invoke('get-destination'),
+  selectDestinationFolder: () => ipcRenderer.invoke('select-destination-folder'),
+  updateDestination: (destination) => ipcRenderer.invoke('update-destination', { destination }),
 });