Improve task date handling to prevent errors

Update task storage logic to correctly format and handle date values for PostgreSQL, preventing potential 500 errors caused by type mismatches and incorrect date parsing.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: cc2d271b-82f0-4d6a-9302-a0b067ffb429
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/1957c339-2757-4d1f-8e92-e9f71a1ce58e/cc2d271b-82f0-4d6a-9302-a0b067ffb429/U0y2tJ3

server/storage.ts

@@ -1724,16 +1724,34 @@ export class DatabaseStorage implements IStorage {
     if (taskData.priority !== undefined) cleanData.priority = taskData.priority;
     if (taskData.status !== undefined) cleanData.status = taskData.status;
     if (taskData.assignedTo !== undefined) cleanData.assignedTo = taskData.assignedTo;
+    
+    // Gestion spéciale des dates selon les types PostgreSQL
     if (taskData.startDate !== undefined) {
-      cleanData.startDate = taskData.startDate === '' || taskData.startDate === null ? null : taskData.startDate;
+      if (taskData.startDate === '' || taskData.startDate === null) {
+        cleanData.startDate = null;
+      } else {
+        // start_date est un timestamp en PostgreSQL - on peut passer une date
+        cleanData.startDate = new Date(taskData.startDate);
+      }
     }
+    
     if (taskData.dueDate !== undefined) {
-      cleanData.dueDate = taskData.dueDate === '' || taskData.dueDate === null ? null : taskData.dueDate;
+      if (taskData.dueDate === '' || taskData.dueDate === null) {
+        cleanData.dueDate = null;
+      } else {
+        // due_date est un date en PostgreSQL - on passe la chaîne directement
+        cleanData.dueDate = taskData.dueDate;
+      }
     }
     
     cleanData.updatedAt = new Date();
     
-    console.log('🧹 Cleaned data for database update:', cleanData);
+    console.log('🧹 Cleaned data for database update:', {
+      ...cleanData,
+      startDateType: cleanData.startDate ? typeof cleanData.startDate : 'null',
+      dueDateType: cleanData.dueDate ? typeof cleanData.dueDate : 'null',
+      startDateIsDate: cleanData.startDate instanceof Date,
+    });
     
     try {
       const [task] = await db