feat(backend): enforce unique names and surface duplicate errors

prisma/migrations/20250930130000_enforce_unique_names/migration.sql

@@ -0,0 +1,16 @@
+-- Drop previous non-unique index to replace it with a unique constraint
+DROP INDEX IF EXISTS "ModelType_category_name_idx";
+
+-- Ensure unique names for machines, components, and pieces
+ALTER TABLE "machines"
+  ADD CONSTRAINT "machines_name_key" UNIQUE ("name");
+
+ALTER TABLE "composants"
+  ADD CONSTRAINT "composants_name_key" UNIQUE ("name");
+
+ALTER TABLE "pieces"
+  ADD CONSTRAINT "pieces_name_key" UNIQUE ("name");
+
+-- Enforce unique category/name pairs for model types (component & piece categories)
+ALTER TABLE "ModelType"
+  ADD CONSTRAINT "ModelType_category_name_key" UNIQUE ("category", "name");

prisma/schema.prisma

@@ -53,7 +53,7 @@ model TypeMachine {
 
 model Machine {
   id        String   @id @default(cuid())
-  name      String
+  name      String   @unique
   reference String?
   prix      Decimal? @db.Decimal(10, 2)
   createdAt DateTime @default(now())
@@ -79,7 +79,7 @@ model Machine {
 
 model Composant {
   id        String   @id @default(cuid())
-  name      String
+  name      String   @unique
   reference String?
   prix      Decimal? @db.Decimal(10, 2)
   createdAt DateTime @default(now())
@@ -101,7 +101,7 @@ model Composant {
 
 model Piece {
   id        String   @id @default(cuid())
-  name      String
+  name      String   @unique
   reference String?
   prix      Decimal? @db.Decimal(10, 2)
   createdAt DateTime @default(now())
@@ -186,7 +186,7 @@ model ModelType {
   pieces                Piece[]                           @relation("ModelTypePieceAssignments")
   pieceCustomFields     CustomField[]                     @relation("ModelTypePieceCustomFields")
 
-  @@index([category, name])
+  @@unique([category, name])
 }
 
 model Constructeur {