zlog: Use zlog as default log implementation (#28612)

Still TODO:

- [x] Remove old log implementations
- [x] More cleanup
- [x] Verify atomic/lock logic
- [x] More tests
- [ ] ??? Ansi coloring when logging to stdout

Release Notes:

- N/A

crates/zlog_settings/src/zlog_settings.rs

@@ -10,7 +10,7 @@ pub fn init(cx: &mut App) {
 
     cx.observe_global::<SettingsStore>(|cx| {
         let zlog_settings = ZlogSettings::get_global(cx);
-        zlog::scope_map::refresh_from_settings(&zlog_settings.scopes);
+        zlog::filter::refresh_from_settings(&zlog_settings.scopes);
     })
     .detach();
 }