Enhance error message for duplicated id

[dayongkr]

Description

Improved the error message when attempting to open multiple overlays with the same overlayId.

Related Issue: Fixes #172

• Why is this change required?
  The original error message did not indicate which overlayId was causing the conflict, making it difficult to debug in complex UI scenarios.

• What problem does it solve?
  Developers can now immediately see which overlayId was duplicated, reducing debugging time.

• Dependencies: None

---

Changes

• Updated the error message in the overlay reducer to include the conflicting overlayId:

  throw new Error(
    `You can't open the multiple overlays with the same overlayId (${action.overlay.id}). Please set a different id.`
  );

---

Motivation and Context

This change was motivated by recurring developer confusion when encountering the "duplicate overlayId" error without enough context. Including the overlayId directly in the error message makes it immediately actionable and improves DX .

---

How Has This Been Tested?

None

---

Screenshots (if appropriate):

Not applicable

---

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

---

Checklist

• I have performed a self-review of my own code.
• My code is commented, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.
• Any dependent changes have been merged and published in downstream modules.

---

Further Comments

None.

[changeset-bot]

🦋 Changeset detected

Latest commit: fd436bb

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
overlay-kit	Patch

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Name	Status	Preview	Comments	Updated (UTC)
overlay-kit	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jun 11, 2025 2:37am

[dayongkr]

While developing a service, I found this error message made debugging a bit difficult, so I created an issue and submitted a PR since the fix seemed straightforward.

If there's already another way to identify the overlayId, please let me know!

[jungpaeng]

Thanks!

[dayongkr]

As you know, due to limitations in our development environment, I wasn’t able to include the changeset file from the forked repository.

I’d really appreciate it if you could commit it. Thanks!!