Add REST API for fetching an account's endorsed accounts (#34421)

config/routes/api.rb

@@ -190,6 +190,7 @@ namespace :api, format: false do
         resources :lists, only: :index
         resources :identity_proofs, only: :index
         resources :featured_tags, only: :index
+        resources :endorsements, only: :index
       end
 
       member do
@@ -203,8 +204,10 @@ namespace :api, format: false do
       end
 
       scope module: :accounts do
-        resource :pin, only: :create
-        post :unpin, to: 'pins#destroy'
+        post :pin, to: 'endorsements#create'
+        post :endorse, to: 'endorsements#create'
+        post :unpin, to: 'endorsements#destroy'
+        post :unendorse, to: 'endorsements#destroy'
         resource :note, only: :create
       end
     end