Generate emoji data from Unicode 17's `emoji-test.txt`, keeping existing
aliases. `public/assets/emoji.json` is now the single emoji data file,
also loaded by the backend. Rendered emoji drop their `aria-label`, the
dark theme inverts key on a new `data-alias` attribute instead.
Skin tone variants and their Gitea-only aliases are removed, GitHub has
none either.
Emoji autocompletion is now lazy-loaded with the markdown editor,
shrinking the index JS chunk from 653KB to 563KB.
---------
Signed-off-by: silverwind <me@silverwind.io>
Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: bircni <bircni@icloud.com>
