enhance(admin): show impersonation banner and keep password change with the user (#38924)

Follow-up to https://github.com/go-gitea/gitea/pull/38614

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

templates/base/head_banner.tmpl

@@ -1,10 +1,10 @@
 {{$banner := ctx.CurrentWebBanner}}
 {{if $banner}}
-<div class="ui info message web-banner-container">
-	<div class="render-content markup web-banner-content">
+<div class="ui info message site-banner-container">
+	<div class="render-content markup site-banner-content">
 		{{ctx.RenderUtils.MarkdownToHtml $banner.ContentMessage}}
 	</div>
-	<button type="button" class="btn dismiss-banner link-action" aria-label="{{ctx.Locale.Tr "dismiss"}}" data-url="{{AppSubUrl}}/-/web-banner/dismiss">
+	<button type="button" class="btn site-banner-close link-action" aria-label="{{ctx.Locale.Tr "dismiss"}}" data-url="{{AppSubUrl}}/-/web-banner/dismiss">
 		{{svg "octicon-x"}}
 	</button>
 </div>

templates/base/head_impersonate_banner.tmpl

@@ -0,0 +1,10 @@
+{{$impersonated := ctx.ImpersonatedUser}}
+{{if $impersonated}}
+<div class="ui warning message site-banner-container">
+	<div class="flex-text-block site-banner-content">
+		{{svg "octicon-alert"}}
+		<span class="tw-flex-1">{{ctx.Locale.Tr "admin.users.impersonating_notice" $impersonated.Name}}</span>
+		<a class="ui compact tiny button hover-opaque" href="{{AppSubUrl}}/user/logout">{{ctx.Locale.Tr "admin.users.impersonate_stop"}}</a>
+	</div>
+</div>
+{{end}}

templates/base/head_navbar.tmpl

@@ -178,4 +178,5 @@
 		</div>
 	</div>
 </nav>
+{{template "base/head_impersonate_banner"}}
 {{template "base/head_banner"}}