Since _ls is now deprecated this is removed in favour of L1, I've also taken the oportunity to replace QStringLiteral and QLatin1String with their shortened form while we're at it.
There are also a few instances where the string literal type has been switch, the general rule being to use the one that matches the function type or value being compared to avoid conversions.
Update the user model so it also sorts by power level and update how we initialize the model to improve performance.
The following is also changed:
- Store a single `UserListModel` in `RoomManager` and use it for everything, this means we don't create extra models (incluiding the long initialisation for each in big rooms)
- By using the single model once it has loaded the users of the new room opening and closing the draw now happens instantly (previously the model would have to be loaded every time the drawer was opened).
- To stop the initial loading and room change of Neochat slowing down (as the `UserListModel` would be loaded before the `TimelineView` is shown) the initialisation of the model is delayed until the `TimelineView` has loaded. This prioritises showing some messages in the timeline over populating the model so in large rooms the user list will initially be blank, but this keeps the initial load snappier.
Add missing #pragma once + missing include
* speeds up incremental builds as changes to a header will not always
need the full mocs_compilation.cpp for all the target's headers rebuild,
while having a moc file sourced into a source file only adds minor
extra costs, due to small own code and the used headers usually
already covered by the source file, being for the same class/struct
* seems to not slow down clean builds, due to empty mocs_compilation.cpp
resulting in those quickly processed, while the minor extra cost of the
sourced moc files does not outweigh that in summary.
Measured times actually improved by some percent points.
(ideally CMake would just skip empty mocs_compilation.cpp & its object
file one day)
* enables compiler to see all methods of a class in same compilation unit
to do some sanity checks
* potentially more inlining in general, due to more in the compilation unit
* allows to keep using more forward declarations in the header, as with the
moc code being sourced into the cpp file there definitions can be ensured
and often are already for the needs of the normal class methods
