feat: Line Channel (#2904)

- Ability to configure line bots as a channel in chatwoot
- Receive a message sent to the line bot in chatwoot
- Ability to reply to line users from chatwoot

fixes: #2738

app/models/channel/line.rb

@@ -0,0 +1,39 @@
+# == Schema Information
+#
+# Table name: channel_line
+#
+#  id                  :bigint           not null, primary key
+#  line_channel_secret :string           not null
+#  line_channel_token  :string           not null
+#  created_at          :datetime         not null
+#  updated_at          :datetime         not null
+#  account_id          :integer          not null
+#  line_channel_id     :string           not null
+#
+# Indexes
+#
+#  index_channel_line_on_line_channel_id  (line_channel_id) UNIQUE
+#
+
+class Channel::Line < ApplicationRecord
+  include Channelable
+
+  self.table_name = 'channel_line'
+  EDITABLE_ATTRS = [:line_channel_id, :line_channel_secret, :line_channel_token].freeze
+
+  validates :line_channel_id, uniqueness: true, presence: true
+  validates :line_channel_secret, presence: true
+  validates :line_channel_token, presence: true
+
+  def name
+    'LINE'
+  end
+
+  def client
+    @client ||= Line::Bot::Client.new do |config|
+      config.channel_id = line_channel_id
+      config.channel_secret = line_channel_secret
+      config.channel_token = line_channel_token
+    end
+  end
+end