Improve issue list layout (#26983)

Align everything with a new layout.

* Use "baseline" for some special elements, the "flex-item-icon" is for
the issue list only at the moment and I think it should be general
enough now (but not using "flex-item-leading" anymore in this case).
* Make the labels stretch themselves.

templates/shared/issuelist.tmpl

@@ -2,16 +2,14 @@
 	{{$approvalCounts := .ApprovalCounts}}
 	{{range .Issues}}
 		<div class="flex-item">
-			<div class="flex-item-leading">
+
+			<div class="flex-item-icon">
 				{{if $.CanWriteIssuesOrPulls}}
-				<div class="flex-item-icon">
 				<input type="checkbox" autocomplete="off" class="issue-checkbox gt-mr-4" data-issue-id={{.ID}} aria-label="{{$.locale.Tr "repo.issues.action_check"}} &quot;{{.Title}}&quot;">
-				</div>
 				{{end}}
-				<div class="flex-item-icon">
 				{{template "shared/issueicon" .}}
 			</div>
-			</div>
+
 			<div class="flex-item-main">
 				<div class="flex-item-header">
 					<div class="flex-item-title">

web_src/css/repo/issue-list.css

@@ -33,6 +33,22 @@
   }
 }
 
+#issue-list .flex-item-title .labels-list {
+  display: flex;
+  gap: 0.25em;
+}
+
+#issue-list .flex-item-title .labels-list a {
+  display: flex;
+  text-decoration: none;
+}
+
+#issue-list .flex-item-title .labels-list .label {
+  padding: 0 6px;
+  margin: 0;
+  min-height: 20px;
+}
+
 #issue-list .flex-item-body .branches {
   display: inline-flex;
 }

web_src/css/shared/flex-list.css

@@ -34,9 +34,11 @@
 }
 
 .flex-item .flex-item-icon {
-  display: flex;
+  align-self: baseline; /* mainly used by the issue list, to align the leading icon with the title */
-  align-items: center;
+}
-  height: 20px; /* match the default flex-item-title height */
+
+.flex-item .flex-item-icon + .flex-item-main {
+  align-self: baseline;
 }
 
 .flex-item .flex-item-trailing {
@@ -59,7 +61,6 @@
   font-weight: var(--font-weight-semibold);
   word-break: break-word;
   min-width: 0;
-  min-height: 20px;
 }
 
 .flex-item .flex-item-title a {