Follow up on trimmed builds

[Tyrrrz]

Stream-line trimmed builds by eliminating warnings and workarounds. Currently, warnings are produced by the following dependencies:

• Avalonia itself
• Material.Avalonia
• CliFx (uses reflection)
• Onova (uses reflection)
• Cogwheel (supports source-generation but doesn't seem to work well)

Related to #1235

[Tyrrrz]

Marking as done because we got full trimming working well in latest versions. AOT is not enabled currently, but its value is dubious as it stands.