fix(frontend): ユーザのサジェスト中に@を入力してもサジェスト結果が消えないように (#15435)

Co-authored-by: syuilo <4439005+syuilo@users.noreply.github.com>

packages/frontend/src/components/MkAutocomplete.vue

@@ -49,6 +49,7 @@ import sanitizeHtml from 'sanitize-html';
 import { emojilist, getEmojiName } from '@@/js/emojilist.js';
 import { char2twemojiFilePath, char2fluentEmojiFilePath } from '@@/js/emoji-base.js';
 import { MFM_TAGS, MFM_PARAMS } from '@@/js/const.js';
+import type { EmojiDef } from '@/scripts/search-emoji.js';
 import contains from '@/scripts/contains.js';
 import { acct } from '@/filters/user.js';
 import * as os from '@/os.js';
@@ -58,7 +59,6 @@ import { i18n } from '@/i18n.js';
 import { miLocalStorage } from '@/local-storage.js';
 import { customEmojis } from '@/custom-emojis.js';
 import { searchEmoji } from '@/scripts/search-emoji.js';
-import type { EmojiDef } from '@/scripts/search-emoji.js';
 
 const lib = emojilist.filter(x => x.category !== 'flags');
 
@@ -198,8 +198,10 @@ function exec() {
 			users.value = JSON.parse(cache);
 			fetching.value = false;
 		} else {
+			const [username, host] = props.q.toString().split('@');
 			misskeyApi('users/search-by-username-and-host', {
-				username: props.q,
+				username: username,
+				host: host,
 				limit: 10,
 				detail: false,
 			}).then(searchedUsers => {