Add zh(Han) translation for Donate page

[Darrenhqf]

This PR adds a zh (Hans) translation for the "Donate" web-page.

It addresses issue #712.

In this document, I have:

• Translated two paragraphs inside <p> tags into Simplified Chinese.
• Added Chinese descriptions to the alt attributes of all images to improve accessibility.
• Ensured that the translated alt text will be displayed correctly in View Alt text mode.

[ksen0]

Thank you @Darrenhqf ! We can merge this PR as soon as another contributor can review.

To anyone reading: If you're a Chinese speaker, please chime in with feedback! One or two comments would be really appreciated.

[lirenjie95]

Approved. @ksen0 Can you help merge this PR? Thank you in advance.

[ksen0]

Thanks @lirenjie95 !