enhance(emoji): update to Unicode 17, unify and lazy-load emoji data (#39363)

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>

web_src/js/utils/match.ts

@@ -1,4 +1,4 @@
-import emojis from '../../../assets/emoji.json' with {type: 'json'};
+import emojis from '../../../public/assets/emoji.json' with {type: 'json'};
 import {GET} from '../modules/fetch.ts';
 import {showErrorToast} from '../modules/toast.ts';
 import {parseIssuePageInfo} from '../utils.ts';