[zh] Sync outdated style and structure of /community page

1. The `/community/_index` page is outdated by comparing to the English version.
2. Not well-formatted and organized, and the style is not consistent with the English version.
3. Tweak some of the translation of `/community/_index` page.

Signed-off-by: Neko Ayaka <[email protected]>

Author: nekomeowww