Add Navigation Buttons and Improve Documentation Titles

[jayesh9747]

Description To improve user experience, add "Prev" and "Next" buttons at the bottom of each documentation page for easy navigation between sections. Additionally, review and update documentation titles to ensure they are clear, descriptive, and consistent for better readability and SEO.

[jayesh9747]

@appleboy I would like to add this feature to the documentation. Can I proceed with this?

[appleboy]

See the new website: https://github.com/gin-gonic/website/pull/289