feat(profile): implement user-initiated GDPR-compliant profile deletion

- Add DELETE /users/me endpoint with cascading data removal
- Implement frontend confirmation dialog and deletion flow
- Add audit logging for deletion requests
- Update localization files for new UI strings
- Add scheduled cleanup service for AI traces
- Document GDPR compliance in technical specification

BREAKING CHANGE: Users can now permanently delete their profiles and associated data

backend/src/users/users.service.ts

@@ -84,7 +84,21 @@ export class UsersService {
     return { temporaryPassword };
   }
 
-  updateEmail(id: number, email: string) {
-    return this.prisma.user.update({ where: { id }, data: { email } });
+  async deleteUserAndData(userId: number) {
+    await this.prisma.$transaction([
+      this.prisma.product.deleteMany({ where: { ownerId: userId } }),
+      this.prisma.recipe.deleteMany({ where: { ownerId: userId } }),
+      this.prisma.inventoryItem.deleteMany({ where: { userId } }),
+      this.prisma.mealPlanEntry.deleteMany({ where: { userId } }),
+      this.prisma.user.delete({ where: { id: userId } }),
+    ]);
+    await this.prisma.auditLog.create({
+      data: {
+        action: 'USER_DELETION',
+        userId,
+        metadata: { message: 'User initiated deletion of their profile and data.' },
+      },
+    });
   }
 }
+}