Challenge 3: Nested Resources Plus a Member Route — Solution

# config/routes.rb
Rails.application.routes.draw do
  resources :products do
    resources :reviews
    member do
      post "feature"
    end
  end
end

Resulting relevant routes (partial list):
GET   /products/:product_id/reviews          reviews#index
POST  /products/:product_id/reviews          reviews#create
GET   /products/:product_id/reviews/:id      reviews#show
...
POST  /products/:id/feature                  products#feature

=begin
Notes:
- resources :reviews, nested inside the resources :products block, scopes
  every review route under a specific product's ID (:product_id) — a
  review can't be requested independently of the product it belongs to,
  matching the reviews-belong-to-a-product relationship.
- member do post "feature" end adds one custom route, POST
  /products/:id/feature, mapped to a feature action Rails expects to find
  on ProductsController. member is used (not collection) because this
  action acts on one specific product, requiring an :id in the URL.
- Both the nested resources and the member block live inside the same
  resources :products do ... end, showing that Rails' block-based routing
  DSL composes naturally — nesting and custom member/collection routes
  aren't mutually exclusive features.
=end