[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/tsconfig.json

@@ -10,14 +10,15 @@
     "types": ["node"],
     "outDir": "../../.cache/tsc",
     "paths": {
-      "@ui/*": ["./src/*"]
+      "@ui/*": ["./src/*"],
+      "@assets/*": ["./src/assets/*"]
     }
   },
   "files": [],
   "include": [],
   "references": [
     {
-      "path": "./tsconfig.build.json"
+      "path": "./tsconfig.lib.json"
     },
     {
       "path": "./tsconfig.dev.json"