feat: Custom accent color (#4897)

* types

* Working, but messy

* Add InputColor component

* types

* Show default theme values when not customized

* Support custom theme on team sign-in page

* Payload validation

* Custom theme on shared documents

* Improve theme validation

* Team -> Workspace in settings

app/components/DocumentExplorerNode.tsx

@@ -117,7 +117,7 @@ export const Node = styled.span<{
   ${(props) =>
     props.selected &&
     `
-      background: ${props.theme.primary};
+      background: ${props.theme.accent};
       color: ${props.theme.white};
 
       svg {