Add default value for clone URLs (go-gitea#20600)

Default clone URLs to HTTP(S) in DOM rendering. JS will immediately
replace this if the user preference is SSH.

Fixes: go-gitea#20558

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

templates/repo/clone_buttons.tmpl

@@ -9,7 +9,7 @@
 		SSH
 	</button>
 {{end}}
-<input id="repo-clone-url" class="js-clone-url" value="" size="1" readonly>
+<input id="repo-clone-url" class="js-clone-url" value="{{$.CloneButtonOriginLink.HTTPS}}" size="1" readonly>
 <button class="ui basic icon button tooltip" id="clipboard-btn" data-content="{{.locale.Tr "copy_url"}}" data-clipboard-target="#repo-clone-url" aria-label="{{.locale.Tr "copy_url"}}">
 	{{svg "octicon-paste"}}
 </button>

templates/repo/empty.tmpl

@@ -37,7 +37,7 @@ git init
 {{if ne .Repository.DefaultBranch "master"}}git checkout -b {{.Repository.DefaultBranch}}{{end}}
 git add README.md
 git commit -m "first commit"
-git remote add origin <span class="js-clone-url"></span>
+git remote add origin <span class="js-clone-url">{{$.CloneButtonOriginLink.HTTPS}}</span>
 git push -u origin {{.Repository.DefaultBranch}}</code></pre>
 								</div>
 							</div>
@@ -46,7 +46,7 @@ git push -u origin {{.Repository.DefaultBranch}}</code></pre>
 							<div class="item">
 								<h3>{{.locale.Tr "repo.push_exist_repo"}}</h3>
 								<div class="markup">
-									<pre><code>git remote add origin <span class="js-clone-url"></span>
+									<pre><code>git remote add origin <span class="js-clone-url">{{$.CloneButtonOriginLink.HTTPS}}</span>
 git push -u origin {{.Repository.DefaultBranch}}</code></pre>
 								</div>
 							</div>