feat: Added the ability to create Instagram channel (#11182)

This PR is part of https://github.com/chatwoot/chatwoot/pull/11054 to
make the review cycle easier.

app/controllers/api/v1/accounts/instagram/authorizations_controller.rb

@@ -0,0 +1,30 @@
+class Api::V1::Accounts::Instagram::AuthorizationsController < Api::V1::Accounts::BaseController
+  include InstagramConcern
+  include Instagram::IntegrationHelper
+  before_action :check_authorization
+
+  def create
+    # https://developers.facebook.com/docs/instagram-platform/instagram-api-with-instagram-login/business-login#step-1--get-authorization
+    redirect_url = instagram_client.auth_code.authorize_url(
+      {
+        redirect_uri: "#{base_url}/instagram/callback",
+        scope: REQUIRED_SCOPES.join(','),
+        enable_fb_login: '0',
+        force_authentication: '1',
+        response_type: 'code',
+        state: generate_instagram_token(Current.account.id)
+      }
+    )
+    if redirect_url
+      render json: { success: true, url: redirect_url }
+    else
+      render json: { success: false }, status: :unprocessable_entity
+    end
+  end
+
+  private
+
+  def check_authorization
+    raise Pundit::NotAuthorizedError unless Current.account_user.administrator?
+  end
+end