fix(db): backfill existing super users to admin role in migration

Add UPDATE statement to promote is_super_user=true rows to role='admin'
before dropping the is_super_user column, preventing silent demotion.

Author: waleedlatif1

packages/db/migrations/0177_wise_puma.sql

@@ -1,5 +1,6 @@
 ALTER TABLE "session" ADD COLUMN "impersonated_by" text;--> statement-breakpoint
 ALTER TABLE "user" ADD COLUMN "role" text DEFAULT 'user';--> statement-breakpoint
+UPDATE "user" SET "role" = 'admin' WHERE "is_super_user" = true;--> statement-breakpoint
 ALTER TABLE "user" ADD COLUMN "banned" boolean DEFAULT false;--> statement-breakpoint
 ALTER TABLE "user" ADD COLUMN "ban_reason" text;--> statement-breakpoint
 ALTER TABLE "user" ADD COLUMN "ban_expires" timestamp;--> statement-breakpoint