fix(backend): make user_devices migration idempotent for fresh DBs

Add CREATE TABLE IF NOT EXISTS for rebreak.user_devices to the
hardware_id migration so fresh databases can migrate despite the
alphabetical ordering mismatch with 20260430_add_user_devices.
Also apply Prettier formatting to mdm.ts.

backend/prisma/migrations/20250616_add_hardware_id_to_user_devices/migration.sql

@@ -1,6 +1,26 @@
 -- Hardware-ID für UserDevices
 -- Client liefert hardwaregebundene ID; Backend speichert sie separat zur bestehenden deviceId.
 
+-- Die canonical CREATE TABLE für user_devices lebt in einer späteren Migration.
+-- Wir erstellen die Tabelle hier idempotent voraus, damit frische Datenbanken
+-- trotz falscher alphabetischer Reihenfolge sauber migrieren.
+CREATE TABLE IF NOT EXISTS "rebreak"."user_devices" (
+    "id"           UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    "user_id"      UUID NOT NULL,
+    "device_id"    TEXT NOT NULL,
+    "platform"     TEXT NOT NULL,
+    "model"        TEXT,
+    "name"         TEXT,
+    "last_seen_at" TIMESTAMP(3) WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "created_at"   TIMESTAMP(3) WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS "user_devices_user_id_device_id_key"
+    ON "rebreak"."user_devices"("user_id", "device_id");
+
+CREATE INDEX IF NOT EXISTS "user_devices_user_id_idx"
+    ON "rebreak"."user_devices"("user_id");
+
 ALTER TABLE "rebreak"."user_devices"
     ADD COLUMN IF NOT EXISTS "hardware_id" TEXT;
 

backend/server/db/mdm.ts

@@ -104,7 +104,9 @@ export async function clearUserDeviceMdmId(
 /**
  * Load all iOS devices that have a NanoMDM UDID link.
  */
-export async function getLinkedUserDevices(): Promise<UserDeviceMdmHealthRecord[]> {
+export async function getLinkedUserDevices(): Promise<
+  UserDeviceMdmHealthRecord[]
+> {
   const db = usePrisma();
   return db.userDevice.findMany({
     where: { platform: "ios", mdmId: { not: null } },