Is your feature request related to a problem? Please describe.
Explicitly wrapping AppUI components in ThemeManager should not be required.
Investigate what it would take to achieve this.
### Tasks
- [ ] Replace `AppUI` CSS variables with `iTwinUI` variables. I.e. `--buic-background-1` should be replaced by `var(--iui-color-background);`. Document that `buic` variables are deprecated, suggest a mapping table for replacements.
- [x] ~~Deprecate `ThemeManager` **before 5.0**. Make sure that `--buic` continues to work, and v2 iTwinUI Provider might be needed as well~~
- [x] Deprecate `--buic` CSS vars (in NextVersion.md, create a mapping table) **before 5.0** https://github.com/iTwin/appui/pull/1029
- [x] Deprecate `$buic-` SCSS variables (in NextVersion.md) **before 5.0** https://github.com/iTwin/appui/pull/1029
Describe the Solution you'd like
ThemeProvider of iTwinUI should be enough instead of currently used ThemeManager.
Is your feature request related to a problem? Please describe.
Explicitly wrapping
AppUI
components inThemeManager
should not be required. Investigate what it would take to achieve this.Describe the Solution you'd like
ThemeProvider
ofiTwinUI
should be enough instead of currently usedThemeManager
.