refactor(products): remove subcategory from Product model and related queries

backend/prisma/schema.prisma

@@ -33,7 +33,6 @@ model Product {
   name           String
   normalizedName String          @unique
   category       String?
-  subcategory    String?
   brand          String?
   canonicalName  String?
   isActive       Boolean         @default(true)

backend/src/products/products.controller.ts

@@ -42,9 +42,8 @@ export class ProductsController {
   @Get()
   findAll(
     @Query('tag') tag?: string,
-    @Query('subcategory') subcategory?: string,
   ) {
-    return this.productsService.findAll({ tag, subcategory });
+    return this.productsService.findAll({ tag });
   }
 
   @Public()

backend/src/products/products.service.ts

@@ -15,12 +15,11 @@ export class ProductsService {
     private readonly categoriesService: CategoriesService,
   ) {}
 
-  async findAll(filters?: { tag?: string; subcategory?: string }) {
+  async findAll(filters?: { tag?: string }) {
     return this.prisma.product.findMany({
       where: {
         isActive: true,
         isPrivate: false,
-        ...(filters?.subcategory ? { subcategory: filters.subcategory } : {}),
         ...(filters?.tag
           ? { tags: { some: { tag: { name: filters.tag } } } }
           : {}),
@@ -165,7 +164,6 @@ export class ProductsService {
       normalizedName?: string;
       canonicalName?: string;
       category?: string | null;
-      subcategory?: string | null;
       brand?: string | null;
       categoryId?: number | null;
     } = {};
@@ -195,10 +193,6 @@ export class ProductsService {
       updateData.category = data.category.trim() || null;
     }
 
-    if (typeof data.subcategory === 'string') {
-      updateData.subcategory = data.subcategory.trim() || null;
-    }
-
     if (typeof data.brand === 'string') {
       updateData.brand = data.brand.trim() || null;
     }