fix: enforce carrier-specific channel group routing

api/prisma/migrations/20260703143000_add_channel_group_carrier/migration.sql

@@ -0,0 +1,3 @@
+ALTER TABLE "SmsChannelGroup" ADD COLUMN "carrier" TEXT NOT NULL DEFAULT 'mobile';
+
+CREATE UNIQUE INDEX "SmsChannelGroupItem_groupId_province_key" ON "SmsChannelGroupItem"("groupId", "province");

api/prisma/migrations/20260703152000_add_application_customer_rate/migration.sql

@@ -0,0 +1 @@
+ALTER TABLE "SmsApplication" ADD COLUMN "customerUnitPrice" INTEGER NOT NULL DEFAULT 0;