unify update site alerts + remove animated background from alerts
Created by: slimsag
Prior to this change update site alerts went through a custom TypeScript UI, which predecated us having the ability to render proper backend-generated site alerts. This change removes the custom TypeScript UI for site alerts, and instead uses the standard backend site alerts.
The alert on the top is before, the alert on the bottom is after:
Notes:
- Removing the animated green "progress bar" background is desirable, and we have heard feedback that this type of animation is exactly the thing users with photosensitive epilepsy and related problems try to avoid.
- The fact the bar was animated before was strange, because nothing was actually happening.
- The fact that these alerts were produced separately from regular site-alerts has long been debt, and made implementing and reasoning about #10843 harder than it should have been for both me and @daxmc99
- Losing the "cloud download icon" is unfortunate in my view, but is consistent with other info-type site alerts we produce and fixing this would be annoying and time-consuming.
- If there are any complaints about the new UI style of this, please clearly state whether you think this should not be merged without addressing those complaints. Addressing style concerns would be a larger undertaking than I have time for and would delay this PR.
@rrhyne @felixfbecker @daxmc99 PTAL
Additionally, this removes the same animated background from a few other alerts we have in our application.