Refactor repo-new.ts (#33070)

1. merge `repo-template.ts` into `repo-new.ts` (they are all for "/repo/create")
2. remove jquery
3. fix an anonying fomantic dropdown bug, see the comment of `onResponseKeepSelectedItem`

web_src/js/index.ts

@@ -34,7 +34,6 @@ import {
 import {initRepoEllipsisButton, initCommitStatuses} from './features/repo-commit.ts';
 import {initRepoTopicBar} from './features/repo-home.ts';
 import {initAdminCommon} from './features/admin/common.ts';
-import {initRepoTemplateSearch} from './features/repo-template.ts';
 import {initRepoCodeView} from './features/repo-code.ts';
 import {initSshKeyFormParser} from './features/sshkey-helper.ts';
 import {initUserSettings} from './features/user-settings.ts';
@@ -193,7 +192,6 @@ onDomReady(() => {
     initRepoPullRequestReview,
     initRepoRelease,
     initRepoReleaseNew,
-    initRepoTemplateSearch,
     initRepoTopicBar,
     initRepoWikiForm,
     initRepository,