* Generate types: do not intersect with Config theme type when generating DefaultTheme
* Merge default theme in ResolvedConfig
* UnwrapResolvables on theme.extend as well
* Apply extend to overrides and default theme
* Omit extend from DefaultTheme
* Relax generic constraints, better generic variable names
* Fall back to ThemeConfig if key not in DefaultTheme
* Split out ThemeConfigCustomizable to avoid anys in ThemeConfigResolved
* Allow custom theme properties
* handle TypeScript error
* apply prettier formatting
* update changelog
* change type name
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Co-authored-by: Nikita Gaidakov <ngaidakov@podfather.com>
Co-authored-by: Robin Malfait <malfait.robin@gmail.com>
