got something working thats only a little hacky

app/api/db/migrations/20210815062510_make_social_card_one_to_one_with_project/migration.sql

@@ -0,0 +1,2 @@
+-- AlterIndex
+ALTER INDEX "SocialCard_projectId_unique" RENAME TO "SocialCard.projectId_unique";

app/api/db/schema.prisma

@@ -65,8 +65,8 @@ model Project {
 
 model SocialCard {
   id          String   @id @default(uuid())
-  projectId   String
-  project     Project   @relation(fields: [projectId], references: [id])
+  projectId   String   @unique
+  project     Project  @relation(fields: [projectId], references: [id])
   createdAt   DateTime @default(now())
   updatedAt   DateTime @updatedAt