handle "_latest" in URL during redirection (#108)

internal/app/ui/templates/partials/cookbook/header.html

@@ -5,7 +5,7 @@ <h1 class="cookbook-headline">
 		</h1>
 	</div>
 	<div class="col-auto">
-		<select class="form-select form-select-sm" id="cookbook-versions-dropdown" onchange="if (this.value) window.location.href=window.location.pathname.replace('{{.cookbook.Metadata.Version}}', this.value)">
+		<select class="form-select form-select-sm" id="cookbook-versions-dropdown" onchange="if (this.value) changeUrl(this.value)">
 			<option selected value="{{ .cookbook.Metadata.Version }}">{{ .cookbook.Metadata.Version }}</option>
 		</select>
 	</div>
@@ -35,6 +35,11 @@ <h1 class="cookbook-headline">
 			selectBox.removeChild(selectBox.firstElementChild)
 		}
 	);
+
+	function changeUrl(v) {
+		const searchTerm = window.location.pathname.includes("/_latest/") ? "/_latest/" : '/{{.cookbook.Metadata.Version}}/'
+		window.location.href = window.location.pathname.replace(searchTerm, '/' + v + '/');
+	}
 </script>
 <div class="col">
 	<ul class="nav nav-tabs justify-content-end">