chore: Add an API to find the contacts using contact inbox sourceId (#8012)

Fixes: https://linear.app/chatwoot/issue/CW-2578/search-by-facebook-id

config/routes.rb

@@ -46,6 +46,11 @@ Rails.application.routes.draw do
           resource :bulk_actions, only: [:create]
           resources :agents, only: [:index, :create, :update, :destroy]
           resources :agent_bots, only: [:index, :create, :show, :update, :destroy]
+          resources :contact_inboxes, only: [] do
+            collection do
+              post :filter
+            end
+          end
           resources :assignable_agents, only: [:index]
           resource :audit_logs, only: [:show]
           resources :callbacks, only: [] do