fix: Ensure unique username in an organization (#15730)

packages/prisma/migrations/20240711080953_unique_username_in_org/migration.sql

@@ -0,0 +1,8 @@
+/*
+  Warnings:
+
+  - A unique constraint covering the columns `[username,organizationId]` on the table `Profile` will be added. If there are existing duplicate values, this will fail.
+
+*/
+-- CreateIndex
+CREATE UNIQUE INDEX "Profile_username_organizationId_key" ON "Profile"("username", "organizationId");

packages/prisma/schema.prisma

@@ -349,7 +349,11 @@ model Profile {
   createdAt      DateTime    @default(now())
   updatedAt      DateTime    @updatedAt
 
+  // A user can have multiple profiles in different organizations
   @@unique([userId, organizationId])
+  // Allow username reuse only across different organizations
+  @@unique([username, organizationId])
+
   @@index([uid])
   @@index([userId])
   @@index([organizationId])