Add rounded style on navigation component.

[CuteLeon]

Description

Add rounded-r-xl style on navigation component.

Issue reference

null

Checklist

• [x] Code compiles correctly
• [x] Created/updated tests
• [x] Extended the documentation

[doddgu]

Thanks for your PR. Please provide the rounded navigation screenshot. This will improve the review efficiency. And why you set it rounded? We designed a outer border for it.

[CuteLeon]

Hi @doddgu , screenshot attached. This improvement is used to make the style of navigation component more uniform with other components.

[doddgu]

@CuteLeon Hi, flat is by design. If you like rounded, you can add a settings for it.

[CuteLeon]

Hi, @doddgu, I Implemented a NavigationStyle config to control navigation bar style. And kept default option as current Flat approach.

[capdiem]

@CuteLeon Indent 8 spaces?

[CuteLeon]

My IDE replaced white-space characters automatically, I have reverted them;

@CuteLeon Indent 8 spaces?

[pccai]

Online Demo cannot setting rounded style？

[capdiem]

@pccai let me check

[capdiem]

@pccai Updated.