feat: Add type to campaign

packages/db/prisma/migrations/20260401164418_add_campaign_type/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "campaigns" ADD COLUMN     "type" "TemplateType" NOT NULL DEFAULT 'MARKETING';

packages/db/prisma/schema.prisma

@@ -291,6 +291,9 @@ model Campaign {
   fromName String?
   replyTo  String?
 
+  // Campaign type
+  type TemplateType @default(MARKETING)
+
   // Audience selection
   audienceType      CampaignAudienceType @default(ALL)
   audienceCondition Json? // For FILTERED: manual filter condition with AND/OR logic (same structure as Segment.condition)