[NEW] Add default chat closing tags in Omnichannel departments

[renatobecker]

CLOSES #16191

The linked issue describes the wrong behavior when closing Omnichannel conversation from users(visitors, system, etc..) other than the agent who is assisting the chat, in conversations associated with a department that requires at least one tag when closing the chat.

Currently, when an agent attempts to close a chat from the web client and the closing process doesn't succeed, they get the following error:

From the agent's side, everything is working as well as expected, but from other sides, such as the livechat widget or other processes performed on the server-side, it doesn't, because the room isn't closed properly due to the current tag's validation.

So, to fix and improve the flow of closing omnichannel chats, a new(and requested) feature has been added in order to avoid unwanted problems:

• Now it's possible to set up conversation closing tags per department, which will be automatically assigned to the rooms when closing the omnichannel chats:

Version with pre-configured Tags(A select component is rendered)

Version with no pre-configured Tags(An input component is rendered)

This new feature is optional when the Request tag (s) before closing the conversation is false, otherwise, it is a mandatory configuration and validation has been added to ensure the expected configuration.

So now, the system will continue validating the rooms before closing, but only the agent(web client) will get an error if there is no tag in the room associated with departments that require tags before closing.
If the validation succeeds, the room tags set by the agent will be merged with the default conversation closing tags of the department(if exists), as shown below: