[REFACTOR] Twenty UI multi barrel (#11301)

# Introduction
closes https://github.com/twentyhq/core-team-issues/issues/591
Same than for `twenty-shared` made in
https://github.com/twentyhq/twenty/pull/11083.

## TODO
- [x] Manual migrate twenty-website twenty-ui imports

## What's next:
- Generate barrel and migration script factorization within own package
+ tests
- Refactoring using preconstruct ? TimeBox
- Lint circular dependencies
- Lint import from barrel and forbid them

### Preconstruct
We need custom rollup plugins addition, but preconstruct does not expose
its rollup configuration. It might be possible to handle this using the
babel overrides. But was a big tunnel.
We could give it a try afterwards ! ( allowing cjs interop and stuff
like that )
Stuck to vite lib app

Closed related PRs:
- https://github.com/twentyhq/twenty/pull/11294
- https://github.com/twentyhq/twenty/pull/11203

packages/twenty-ui/src/display/icon/components/IconRelationManyToOne.tsx

@@ -1,6 +1,6 @@
 import { useTheme } from '@emotion/react';
 
-import IconRelationManyToOneRaw from '@ui/display/icon/assets/many-to-one.svg?react';
+import IconRelationManyToOneRaw from '@assets/icons/many-to-one.svg?react';
 import { IconComponentProps } from '@ui/display/icon/types/IconComponent';
 
 type IconRelationManyToOneProps = Pick<IconComponentProps, 'size' | 'stroke'>;