feat(steps): 支持 separator api & 完善反转逻辑

[honkinglin]

🤔 这个 PR 的性质是？

• 日常 bug 修复
• 新特性提交
• 文档改进
• 演示代码改进
• 组件样式/交互改进
• CI/CD 改进
• 重构
• 代码风格优化
• 测试用例
• 分支合并
• 其他

🔗 相关 Issue

💡 需求背景和解决方案

📝 更新日志

• feat(Steps): 支持 separator api & 完善反转逻辑

• 本条 PR 不需要纳入 Changelog

☑️ 请求合并前的自查清单

⚠️ 请自检并全部勾选全部选项。⚠️

• 文档已补充或无须补充
• 代码演示已提供或无须提供
• TypeScript 定义已补充或无须补充
• Changelog 已提供或无须提供

[github-actions]

Size Change: -82 B (0%)

Total Size: 642 kB

Filename	Size	Change
./dist/tdesign.js	356 kB	-59 B (0%)
./dist/tdesign.min.js	204 kB	-23 B (0%)

ℹ️ View Unchanged

Filename	Size
./dist/tdesign.css	43.4 kB
./dist/tdesign.min.css	38.6 kB

[codecov-commenter]

Codecov Report

Merging #868 (92aec7e) into develop (a0db0df) will increase coverage by 3.81%.
The diff coverage is 67.63%.

@@             Coverage Diff             @@
##           develop     #868      +/-   ##
===========================================
+ Coverage    57.56%   61.37%   +3.81%     
===========================================
  Files          346      355       +9     
  Lines        12828    13467     +639     
  Branches      2405     2567     +162     
===========================================
+ Hits          7384     8266     +882     
+ Misses        5200     4940     -260     
- Partials       244      261      +17     

Impacted Files	Coverage Δ
src/avatar/group.tsx	97.14% <ø> (ø)
src/breadcrumb/breadcrumb-item-props.ts	100.00% <ø> (ø)
src/calendar/props.ts	70.00% <0.00%> (-30.00%)	⬇️
src/cascader/props.ts	91.66% <ø> (ø)
src/cascader/utils/inputContent.ts	59.45% <0.00%> (+6.68%)	⬆️
src/date-picker/date-picker.tsx	46.57% <0.00%> (+0.72%)	⬆️
src/date-picker/panel/date-range.tsx	7.48% <0.00%> (+0.29%)	⬆️
src/dialog/props.ts	70.00% <0.00%> (-30.00%)	⬇️
src/dropdown/dropdown-menu.tsx	18.42% <ø> (ø)
src/dropdown/dropdown.tsx	70.00% <0.00%> (+5.00%)	⬆️
... and 133 more

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[github-actions]

[github-actions]

Size Change: -82 B (0%)

Total Size: 642 kB

Filename	Size	Change
./dist/tdesign.js	356 kB	-59 B (0%)
./dist/tdesign.min.js	204 kB	-23 B (0%)

ℹ️ View Unchanged

Filename	Size
./dist/tdesign.css	43.4 kB
./dist/tdesign.min.css	38.6 kB

[github-actions]

Size Change: -82 B (0%)

Total Size: 642 kB

Filename	Size	Change
./dist/tdesign.js	356 kB	-59 B (0%)
./dist/tdesign.min.js	204 kB	-23 B (0%)

ℹ️ View Unchanged

Filename	Size
./dist/tdesign.css	43.5 kB
./dist/tdesign.min.css	38.6 kB