**This PR creates a new core reusable component wraps a character counter around any input.**
The component accepts the arguments: `max` (the maximum character limit), `value` (the value of text to be monitored).
It can be used for example, like so:
```hbs
<CharCounter @max="50" @value={{this.charCounterContent}}>
<textarea
placeholder={{i18n "styleguide.sections.char_counter.placeholder"}}
{{on "input" (action (mut this.charCounterContent) value="target.value")}}
class="styleguide--char-counter"></textarea>
</CharCounter>
```
**This PR also:**
1. Applies this component to the chat plugins edit channel's *Edit Description** modal, thereby replacing the simple text area which provided no visual indication when text exceeded the max allowed characters.
2. Adds an example to the `/styleguide` route
This commit introduces the ability to edit the channel
slug from the About tab for the chat channel when the user
is admin. Similar to the create channel modal functionality
introduced in 641e94f, if
the slug is left empty then we autogenerate a slug based
on the channel name, and if the user just changes the slug
manually we use that instead.
We do not do any link remapping or anything else of the
sort, when the category slug is changed that does not happen
either.
We refer to the channel name rather than title elsewhere
(including the new channel modal), so we should be consistent.
Title is an internal abstraction, since DM channels cannot have
names (currently).
Also change the name field on channel edit to a input type="text"
rather than a textarea, since we don't want a huge input here.
The settings tab of each category channel should now present the option to allow or disallow channel wide mentions: @here and @all.
When disallowed, using these mentions in the channel should have no effect.
- Note this is also tweaking the UI a little bit as we are now using links/buttons in the header as needed
- It disables the find ideal channel in drawer mode, if loading `/chat` in drawer mode it will either reopen at the last position or just stay on index
Toggling channel settings shows a status message when saved. This status message is not accessible to screen readers. This commit ensures that the status message is made accessible.
