Add tabIndex() method to Button widget

[Mister-42]

Q	A
Is bugfix?	❌
New feature?	✔️
Breaks BC?	❌
Tests pass?	✔️
Fixed issues

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (d3d3ace) to head (728b47d).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##              master      #305   +/-   ##
===========================================
  Coverage     100.00%   100.00%           
- Complexity       711       712    +1     
===========================================
  Files             22        22           
  Lines           2934      2936    +2     
===========================================
+ Hits            2934      2936    +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[samdark]

@Mister-42 please check Psalm.

[Copilot]

Pull request overview

Adds a tabIndex() fluent API to the Yiisoft\Bootstrap5\Button widget so consumers can set the HTML tabindex attribute directly when rendering buttons.

Changes:

• Add Button::tabIndex(?int $value) that maps to the tabindex HTML attribute.
• Add a PHPUnit test asserting tabindex="42" is rendered on the button.
• Update CHANGELOG.md to document the enhancement.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/Button.php	Introduces the tabIndex() method and documents tabindex behavior.
tests/ButtonTest.php	Adds coverage to verify tabindex is rendered as expected.
CHANGELOG.md	Records the new feature under the upcoming release.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Mister-42]

@Mister-42 please check Psalm.

As far as I can see all Psalm errors are caused by deprecation, not introduced by me. Correct me if I'm wrong.

[samdark]

Yes. You're correct.

[samdark]

Thank you!