feat(Layout): add prop zeroWidthTriggerStyle

[orzyyyy]

🤔 This is a ...

• New feature
• Bug fix
• Site / document update
• Component style update
• TypeScript definition update
• Refactoring
• Code style optimization
• Test Case
• Branch merge
• Other (about what?)

🔗 Related issue link

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	add prop specialTriggerStyle to controll the style of the special trigger that appears when collapsedWidth is 0.
🇨🇳 Chinese	新增属性 specialTriggerStyle 以控制当 collapsedWidth 为 0 时，出现的特殊 trigger 的样式。

☑️ Self Check before Merge

• Doc is updated/provided or not needed
• Demo is updated/provided or not needed
• TypeScript definition is updated/provided or not needed
• Changelog is provided or not needed

[tests-checker]

Could you please add tests to make sure this change works as expected?

[netlify]

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[orzyyyy]

/rebase

[afc163]

/rebase

[codecov]

Codecov Report

Merging #19079 into feature will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           feature   #19079   +/-   ##
========================================
  Coverage    97.76%   97.76%           
========================================
  Files          281      281           
  Lines         7605     7605           
  Branches      2135     2135           
========================================
  Hits          7435     7435           
  Misses         170      170

Impacted Files	Coverage Δ
components/layout/Sider.tsx	95.6% <ø> (ø)	⬆️

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[afc163]

zeroWidthTriggerStyle