i18n(zh-cn): Delete some outdated links and abandon a document that is not maintained

[mogeko]

What kind of changes does this PR include?

• Minor content fixes (broken links, typos, etc.)
• Changes to the docs site code

Description

Removed 2 duplicate links and removed 3 outdated links for ui.ts and nav.ts. #635 #893

Update "unmaintained content" aside for comparing-astro-vs-other-tools.md. #1264

This PR is some small optimization, but if it is labeled with hacktoberfest-accepted, I will be very happy. 😘

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