[Performance] Optimize getArrayContainsDuplicates with early exit

[gonzaloriestra]

WHY are these changes introduced?

The current implementation of getArrayContainsDuplicates always processes the entire array to create a Set, even if a duplicate is found early on. This is inefficient for large arrays with early duplicates.

WHAT is this pull request doing?

Refactors getArrayContainsDuplicates to use a for...of loop and a Set to track seen elements, allowing it to return true immediately when a duplicate is encountered.

How to test your changes?

CI

Post-release steps

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes
• I've considered analytics changes to measure impact
• The change is user-facing — I've identified the correct bump type (patch for bug fixes · minor for new features · major for breaking changes) and added a changeset with pnpm changeset add

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PR created automatically by Jules for task 12501024952324881799 started by @gonzaloriestra

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[github-actions]

Differences in type declarations

We detected differences in the type declarations generated by Typescript for this branch compared to the baseline ('main' branch). Please, review them to ensure they are backward-compatible. Here are some important things to keep in mind:

• Some seemingly private modules might be re-exported through public modules.
• If the branch is behind main you might see odd diffs, rebase main into this branch.

New type declarations

We found no new type declarations in this PR

Existing type declarations

packages/cli-kit/dist/public/common/array.d.ts

@@ -16,6 +16,10 @@ export declare function getArrayRejectingUndefined<T>(array: (T | undefined)[]):
 /**
  * Returns true if an array contains duplicates.
  *
+ * This implementation is optimized to exit early as soon as the first duplicate
+ * is found, avoiding unnecessary processing of the rest of the array.
+ * Time complexity: O(k) where k is the index of the first duplicate, O(n) otherwise.
+ *
  * @param array - The array to check against.
  * @returns True if the array contains duplicates.
  */