feat: Backend - Companies API endpoint with pagination and search (#12840)

## Description

Adds API endpoint to list companies with pagination, search, and
sorting.

Fixes
https://linear.app/chatwoot/issue/CW-5930/add-backend-routes-to-get-companies-result
Parent issue:
https://linear.app/chatwoot/issue/CW-5928/add-companies-tab-to-dashboard

## Type of change

- [x] New feature (non-breaking change which adds functionality)

## How Has This Been Tested?

Added comprehensive specs to
`spec/enterprise/controllers/api/v1/accounts/companies_controller_spec.rb`:
- Pagination (25 per page, multiple pages)
- Search by name and domain (case-insensitive)
- Counter cache for contacts_count
- Account scoping
- Authorization

To reproduce:
```bash
bundle exec rspec spec/enterprise/controllers/api/v1/accounts/companies_controller_spec.rb
bundle exec rubocop enterprise/app/controllers/api/v1/accounts/companies_controller.rb
```

## Checklist:

- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [ ] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules

---------

Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>
Co-authored-by: iamsivin <iamsivin@gmail.com>
Co-authored-by: Shivam Mishra <scm.mymail@gmail.com>
Co-authored-by: Sojan Jose <sojan@pepalo.com>

enterprise/app/controllers/api/v1/accounts/companies_controller.rb

@@ -1,9 +1,29 @@
 class Api::V1::Accounts::CompaniesController < Api::V1::Accounts::EnterpriseAccountsController
+  include Sift
+  sort_on :name, type: :string
+  sort_on :domain, type: :string
+  sort_on :created_at, type: :datetime
+
+  RESULTS_PER_PAGE = 25
+
   before_action :check_authorization
+  before_action :set_current_page, only: [:index, :search]
   before_action :fetch_company, only: [:show, :update, :destroy]
 
   def index
-    @companies = Current.account.companies.ordered_by_name
+    @companies = fetch_companies(resolved_companies)
+    @companies_count = @companies.total_count
+  end
+
+  def search
+    if params[:q].blank?
+      return render json: { error: I18n.t('errors.companies.search.query_missing') },
+                    status: :unprocessable_entity
+    end
+
+    companies = resolved_companies.search_by_name_or_domain(params[:q])
+    @companies = fetch_companies(companies)
+    @companies_count = @companies.total_count
   end
 
   def show; end
@@ -24,6 +44,20 @@ class Api::V1::Accounts::CompaniesController < Api::V1::Accounts::EnterpriseAcco
 
   private
 
+  def resolved_companies
+    @resolved_companies ||= Current.account.companies
+  end
+
+  def set_current_page
+    @current_page = params[:page] || 1
+  end
+
+  def fetch_companies(companies)
+    filtrate(companies)
+      .page(@current_page)
+      .per(RESULTS_PER_PAGE)
+  end
+
   def check_authorization
     raise Pundit::NotAuthorizedError unless ChatwootApp.enterprise?
 

enterprise/app/models/company.rb

@@ -2,13 +2,14 @@
 #
 # Table name: companies
 #
-#  id          :bigint           not null, primary key
-#  description :text
-#  domain      :string
-#  name        :string           not null
-#  created_at  :datetime         not null
-#  updated_at  :datetime         not null
-#  account_id  :bigint           not null
+#  id             :bigint           not null, primary key
+#  contacts_count :integer
+#  description    :text
+#  domain         :string
+#  name           :string           not null
+#  created_at     :datetime         not null
+#  updated_at     :datetime         not null
+#  account_id     :bigint           not null
 #
 # Indexes
 #
@@ -31,4 +32,7 @@ class Company < ApplicationRecord
   has_many :contacts, dependent: :nullify
 
   scope :ordered_by_name, -> { order(:name) }
+  scope :search_by_name_or_domain, lambda { |query|
+    where('name ILIKE :search OR domain ILIKE :search', search: "%#{query.strip}%")
+  }
 end

enterprise/app/models/enterprise/concerns/contact.rb

@@ -1,7 +1,7 @@
 module Enterprise::Concerns::Contact
   extend ActiveSupport::Concern
   included do
-    belongs_to :company, optional: true
+    belongs_to :company, optional: true, counter_cache: true
 
     after_commit :associate_company_from_email,
                  on: [:create, :update],

enterprise/app/policies/company_policy.rb

@@ -3,6 +3,10 @@ class CompanyPolicy < ApplicationPolicy
     true
   end
 
+  def search?
+    true
+  end
+
   def show?
     true
   end

enterprise/app/services/contacts/company_association_service.rb

@@ -3,12 +3,13 @@ class Contacts::CompanyAssociationService
     return nil if skip_association?(contact)
 
     company = find_or_create_company(contact)
-    # rubocop:disable Rails/SkipsModelValidations
-    # Intentionally using update_column here to:
-    # 1. Avoid triggering callbacks
-    # 2. Improve performance (We're only setting company_id, no need for validation)
-    contact.update_column(:company_id, company.id) if company
-    # rubocop:enable Rails/SkipsModelValidations
+    if company
+      # rubocop:disable Rails/SkipsModelValidations
+      # Using update_column and increment_counter to avoid triggering callbacks while maintaining counter cache
+      contact.update_column(:company_id, company.id)
+      Company.increment_counter(:contacts_count, company.id)
+      # rubocop:enable Rails/SkipsModelValidations
+    end
     company
   end
 

enterprise/app/views/api/v1/accounts/companies/_company.json.jbuilder

@@ -1,5 +1,6 @@
 json.id company.id
 json.name company.name
+json.contacts_count company.contacts_count
 json.domain company.domain
 json.description company.description
 json.avatar_url company.avatar_url

enterprise/app/views/api/v1/accounts/companies/index.json.jbuilder

@@ -1,3 +1,8 @@
+json.meta do
+  json.total_count @companies_count
+  json.page @current_page
+end
+
 json.payload do
   json.array! @companies do |company|
     json.partial! 'company', company: company

enterprise/app/views/api/v1/accounts/companies/search.json.jbuilder

@@ -0,0 +1,10 @@
+json.meta do
+  json.total_count @companies_count
+  json.page @current_page
+end
+
+json.payload do
+  json.array! @companies do |company|
+    json.partial! 'company', company: company
+  end
+end