[FIX] Omnichannel enabled setting not working when creating rooms (#24067)

* Fix omnichannel enabled setting not working when creating rooms

* Revert changes to translation file

* Apply suggestions from code review

app/livechat/server/lib/Livechat.js

@@ -156,6 +156,9 @@ export const Livechat = {
 	},
 
 	async getRoom(guest, message, roomInfo, agent, extraData) {
+		if (!this.enabled()) {
+			throw new Meteor.Error('error-omnichannel-is-disabled');
+		}
 		Livechat.logger.debug(`Attempting to find or create a room for visitor ${guest._id}`);
 		let room = LivechatRooms.findOneById(message.rid);
 		let newRoom = false;

app/settings/server/CachedSettings.ts

@@ -220,6 +220,7 @@ export class CachedSettings
 	 * Gets the current value of the setting
 	 * @remarks
 	 * 		- In development mode if you are trying to get the value of a setting that is not defined, it will give an warning, in theory it makes sense, there no reason to do that
+	 * 		- The setting's value will be cached in memory so it won't call the DB every time you fetch a particular setting
 	 * @param _id - The setting id
 	 * @returns {SettingValue} - The current value of the setting
 	 */