chore: add script to generate twenty-ui barrels before build (#4707)

Split from https://github.com/twentyhq/twenty/pull/4518

Part of #4766 

Adds a script to auto-generate twenty-ui exports in `index.ts` files.

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Co-authored-by: Lucas Bordeau <bordeau.lucas@gmail.com>

packages/twenty-ui/src/components/index.ts

@@ -1 +1 @@
-export { Pill } from './Pill/Pill';
+export * from './Pill/Pill';