Optimize falukantService and DirectorInfo component for improved performance and user experience

- Refactored proposal handling in falukantService to load existing proposals before cleaning expired ones, reducing unnecessary database queries.
- Enhanced fetchProposals method with explicit joins for better performance and added a limit to avoid excessive data retrieval.
- Updated DirectorInfo component to reload data after hiring a director, ensuring the UI reflects the latest information.

frontend/src/components/falukant/DirectorInfo.vue

@@ -181,7 +181,7 @@
       </div>
     </div>
   </div>
-  <NewDirectorDialog ref="newDirectorDialog" />
+  <NewDirectorDialog ref="newDirectorDialog" @directorHired="handleDirectorHired" />
 </template>
 
 <script>
@@ -276,6 +276,11 @@ export default {
       this.$refs.newDirectorDialog.open(this.branchId);
     },
 
+    async handleDirectorHired() {
+      // Nach dem Einstellen eines Direktors die Daten neu laden
+      await this.loadDirector();
+    },
+
     async updateDirector() {
       if (!this.director || this.editIncome == null) return;
       try {