5179: Add loglevel config (fixes#5178, fixes#5174) r=heinrich5991 a=def-
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## Checklist
- [x] Tested the change ingame
- [ ] Provided screenshots if it is a visual change
- [ ] Tested in combination with possibly related configuration options
- [ ] Written a unit test if it works standalone, system.c especially
- [ ] Considered possible null pointers and out of bounds array indexing
- [ ] Changed no physics that affect existing maps
- [ ] Tested the change with [ASan+UBSan or valgrind's memcheck](https://github.com/ddnet/ddnet/#using-addresssanitizer--undefinedbehavioursanitizer-or-valgrinds-memcheck) (optional)
Co-authored-by: def <dennis@felsin9.de>
This makes the "black console window" less important on Windows (or
anywhere else, for that matter), lets you see logs from other threads in
the f1 console, and removes the distinction between `IConsole::Print`
and `dbg_msg`.
