- moves the onebox logic away from `plugin.rb` to a new `onebox_handler` lib
- splits the `discourse_chat_message` template into two: one for channels, and one for messages
- refactors the logic code slightly to send only the necessary arguments to each template
This commit shouldn't change end-user behavior.
* DEV: Rnemae channel path to just c
Also swap the channel id and channel slug params to be consistent with core.
* linting
* channel_path
* params in wrong order
* Drop slugify helper and channel route without slug
* Request slug and route models through the channel model if possible
* Add client side redirection for backwards-compatibility
Co-authored-by: Joffrey JAFFEUX <j.jaffeux@gmail.com>