fix: allow deleting users by reassigning their records to admin first

Deleting users with patients/appointments/claims was blocked by FK
constraints. Now reassigns those records to the requesting admin before
deletion, and cleans up user-specific data (backups, cloud files).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/Backend/src/routes/users.ts

@@ -137,6 +137,22 @@ router.delete("/:id", async (req: Request, res: Response):Promise<any> => {
     const id = parseInt(idParam);
     if (isNaN(id)) return res.status(400).send("Invalid user ID");
 
+    if (id === req.user!.id) return res.status(400).json({ error: "Cannot delete your own account" });
+
+    const adminId = req.user!.id;
+
+    // Reassign all records owned by this user to the requesting admin
+    // before deletion to satisfy foreign key constraints.
+    const { prisma } = await import("@repo/db/client");
+    await prisma.$transaction([
+      prisma.patient.updateMany({ where: { userId: id }, data: { userId: adminId } }),
+      prisma.appointment.updateMany({ where: { userId: id }, data: { userId: adminId } }),
+      prisma.claim.updateMany({ where: { userId: id }, data: { userId: adminId } }),
+      prisma.backupDestination.deleteMany({ where: { userId: id } }),
+      prisma.cloudFile.deleteMany({ where: { userId: id } }),
+      prisma.cloudFolder.deleteMany({ where: { userId: id } }),
+    ]);
+
     const success = await storage.deleteUser(id);
     if (!success) return res.status(404).send("User not found");