Trust Decoration | Identity changes, rules for consistent ordering of violation banners on clients

[BillCarsonFr]

As part of the Trust & Decoration work, clients will now display Identity Violations as a banner on top of the composer, for example:

As per current design, we can only display one violation at a time (Notice that there is a proposal to put some violation in the timeline #2493 that could change this fact)

These violation can be of two types:

• Pinning violation (a pinned identity has changed)
• Verification Violation (an identity that was previously verified is not anymore)

We want as much as possible to provide consistency across devices of the same user when displaying these banner.
The rules are the following.

1. Verification Violation should be displayed before Pinning Violation
2. Violation should be ordered by mxId (lexicographical order)
3. If a violation is currently displayed it should stay on until resolved even if a new violation that has more priority is detected (to avoid flickering effect)