feat: implement product categories with tabbed filtering and admin configuration

shop/lib/actions/products.ts

@@ -8,13 +8,24 @@ export async function getProducts() {
   const supabase = await createClient()
   const { data, error } = await supabase
     .from('products')
-    .select('*, modules:product_modules(*)')
+    .select('*, category:categories(*), modules:product_modules(*)')
     .order('created_at', { ascending: false })
 
   if (error) throw error
   return data as Product[]
 }
 
+export async function getCategories() {
+  const supabase = await createClient()
+  const { data, error } = await supabase
+    .from('categories')
+    .select('*')
+    .order('name', { ascending: true })
+
+  if (error) throw error
+  return data
+}
+
 export async function createProduct(product: Omit<Product, 'id' | 'created_at' | 'updated_at'>, modules: Omit<ProductModule, 'id' | 'product_id' | 'created_at'>[]) {
   const supabase = await createClient()
 
@@ -59,8 +70,10 @@ export async function updateProduct(id: string, product: Partial<Product>, modul
     const modulesWithId = modules.map(m => ({
       name: m.name,
       description: m.description,
-      additional_price: m.additional_price,
+      price: m.additional_price, // Match schema column name 'price'
       is_required: m.is_required,
+      requirements: m.requirements || [],
+      exclusions: m.exclusions || [],
       product_id: id
     }))
     const { error: modulesError } = await supabase