feat: added a warning pop-up when openning projects.

src/components/Toolbar.tsx

@@ -205,19 +205,28 @@ const Toolbar: React.FC = () => {
   };
 
   const handleOpenProjectSelect = async (projectNameToLoad: string) => {
+    const confirmed = await showConfirm(
+      'Open this project? Any unsaved changes in the current project will be lost.'
+    );
+    if (!confirmed) {
+      return false;
+    }
+
     try {
       const storage = KGProjectStorage.getInstance();
       const loadedProject = await storage.load(projectNameToLoad);
 
       if (!loadedProject) {
         await showAlert(`Project "${projectNameToLoad}" not found.`);
-        return;
+        return false;
       }
 
       await loadProjectFromData(loadedProject, `Project "${projectNameToLoad}"`, projectNameToLoad);
+      return true;
     } catch (error) {
       console.error("Error loading project:", error);
       await showAlert(`An error occurred while loading the project: ${error}`);
+      return false;
     }
   };
 

src/components/common/OpenProjectModal.tsx

@@ -7,7 +7,7 @@ import { showAlert, showConfirm, showPrompt } from '../../util/dialogUtil';
 
 interface OpenProjectModalProps {
   onClose: () => void;
-  onOpenProject: (projectName: string) => Promise<void>;
+  onOpenProject: (projectName: string) => Promise<boolean>;
   currentProjectName: string | null;
   onCreateNewProject: () => void;
 }
@@ -121,8 +121,10 @@ const OpenProjectModal: React.FC<OpenProjectModalProps> = ({ onClose, onOpenProj
   }, [projects, filter, sortField, sortDirection]);
 
   const handleOpen = async (projectName: string) => {
-    await onOpenProject(projectName);
+    const opened = await onOpenProject(projectName);
+    if (opened) {
       startClose();
+    }
   };
 
   const handleDuplicate = async (e: React.MouseEvent, projectName: string) => {
@@ -140,8 +142,10 @@ const OpenProjectModal: React.FC<OpenProjectModalProps> = ({ onClose, onOpenProj
       const storage = KGProjectStorage.getInstance();
       const finalName = await storage.resolveUniqueName(trimmed);
       await storage.duplicate(projectName, finalName);
-      await onOpenProject(finalName);
+      const opened = await onOpenProject(finalName);
+      if (opened) {
         startClose();
+      }
     } catch (error) {
       console.error('Error duplicating project:', error);
       await showAlert(`Failed to duplicate project: ${error}`);