Add moderation API (#9387)

Fix #8580
Fix #7143

app/controllers/api/v1/admin/account_actions_controller.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+class Api::V1::Admin::AccountActionsController < Api::BaseController
+  before_action -> { doorkeeper_authorize! :'admin:write', :'admin:write:accounts' }
+  before_action :require_staff!
+  before_action :set_account
+
+  def create
+    account_action                 = Admin::AccountAction.new(resource_params)
+    account_action.target_account  = @account
+    account_action.current_account = current_account
+    account_action.save!
+
+    render_empty
+  end
+
+  private
+
+  def set_account
+    @account = Account.find(params[:account_id])
+  end
+
+  def resource_params
+    params.permit(
+      :type,
+      :report_id,
+      :warning_preset_id,
+      :text,
+      :send_email_notification
+    )
+  end
+end