fix(module:range-picker): clear outline on mouse leave

[keke521jie]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/NG-ZORRO/ng-zorro-antd/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Application (the showcase website) / infrastructure changes
• Other... Please describe:

What is the current behavior?

Issue Number: close #6323

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[codecov]

Codecov Report

❌ Patch coverage is 42.85714% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.07%. Comparing base (d878658) to head (c92854e).
⚠️ Report is 8 commits behind head on master.

Files with missing lines	Patch %	Lines
...mponents/date-picker/date-range-popup.component.ts	50.00%	2 Missing ⚠️
components/date-picker/inner-popup.component.ts	33.33%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #9352      +/-   ##
==========================================
- Coverage   92.09%   92.07%   -0.02%     
==========================================
  Files         561      561              
  Lines       19652    19658       +6     
  Branches     3004     3005       +1     
==========================================
+ Hits        18099    18101       +2     
- Misses       1216     1220       +4     
  Partials      337      337              

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[Copilot]

Pull Request Overview

This PR clears the hover outline effect in the range picker component when the mouse leaves the popup area. It addresses issue #6323 by ensuring that range selection visual feedback is properly cleared when the user moves their cursor away from the date picker.

• Adds a mouseleave event handler to the main popup container
• Implements onLeave() method to emit the last selected date on mouse leave
• Ensures proper cleanup of hover states for better user experience

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[Copilot]

[nitpick] Using void 0 instead of undefined is unnecessarily obscure. Consider using undefined for better readability.

Suggested change

	const lastSelectedDate = this.selectedValue.length > 0 ? this.selectedValue[this.selectedValue.length - 1] : void 0;
	const lastSelectedDate = this.selectedValue.length > 0 ? this.selectedValue[this.selectedValue.length - 1] : undefined;

[Copilot]

The onLeave() method lacks documentation. Add a JSDoc comment explaining its purpose of clearing hover states when the mouse leaves the picker area.

[Nicoss54]

LGTM

[Laffery]

LGTM