fix: focus confirm button and use red for delete confirmations (#39350)

Fixes https://github.com/go-gitea/gitea/issues/39347

1. Focus the confirm button in generic confirm modals so `Enter` runs
the highlighted action.
2. Delete actions that lacked the risky flag now get it, so their
confirm button is red.

---------

Co-authored-by: silverwind <me@silverwind.io>

templates/repo/issue/labels/label_list.tmpl

@@ -51,7 +51,7 @@
 							data-label-num-issues="{{.NumIssues}}" data-label-description="{{.Description}}"
 							data-label-exclusive-order="{{.ExclusiveOrder}}"
 						>{{svg "octicon-pencil"}} {{ctx.Locale.Tr "repo.issues.label_edit"}}</a>
-						<a class="link-action" href="#" data-url="{{$.Link}}/delete?id={{.ID}}"
+						<a class="link-action negative" href="#" data-url="{{$.Link}}/delete?id={{.ID}}"
 							data-modal-confirm-header="{{ctx.Locale.Tr "repo.issues.label_deletion"}}"
 							data-modal-confirm-content="{{ctx.Locale.Tr "repo.issues.label_deletion_desc"}}"
 						>{{svg "octicon-trash"}} {{ctx.Locale.Tr "repo.issues.label_delete"}}</a>

templates/repo/issue/view_content/comments_delete_time.tmpl

@@ -2,7 +2,7 @@
 	{{if (not .comment.Time.Deleted)}}
 		{{if (or ctx.RootData.IsAdmin (and ctx.RootData.IsSigned (eq ctx.RootData.SignedUserID .comment.PosterID)))}}
 			<span class="tw-ml-auto">
-				<button type="button" class="ui icon button compact mini link-action" data-tooltip-content="{{ctx.Locale.Tr "repo.issues.del_time"}}"
+				<button type="button" class="ui icon button compact mini link-action negative" data-tooltip-content="{{ctx.Locale.Tr "repo.issues.del_time"}}"
 								data-url="{{ctx.RootData.RepoLink}}/issues/{{ctx.RootData.Issue.Index}}/times/{{.comment.TimeID}}/delete?id={{.comment.Time.ID}}"
 								data-modal-confirm="{{ctx.Locale.Tr "repo.issues.del_time"}}"
 				>