feat: show live build version in web UI

- /api/version returns version, commitSha, buildDate, trashRetentionDays
- CI passes COMMIT_SHA (full), BUILD_DATE and VERSION (git tag) as
  docker build args; Dockerfile bakes them as env
- sidebar footer shows version/sha linked to the Gitea commit
- admin System tab shows version, commit link, build date, trash retention

artifacts/toolrate/src/components/layout.tsx

@@ -1,6 +1,7 @@
 import { Link, useLocation } from "wouter";
 import { LayoutDashboard, Wrench, PlusCircle, BarChart3, LogIn, LogOut, User, ShieldCheck, AlertTriangle, Trash2 } from "lucide-react";
 import { useAuth } from "@/hooks/use-auth";
+import { useGetVersion, getGetVersionQueryKey } from "@workspace/api-client-react";
 import { Button } from "@/components/ui/button";
 import { Skeleton } from "@/components/ui/skeleton";
 import { ThemeToggle } from "@/components/theme-toggle";
@@ -8,6 +9,9 @@ import { ThemeToggle } from "@/components/theme-toggle";
 export function Layout({ children }: { children: React.ReactNode }) {
   const [location] = useLocation();
   const { user, isLoading, isAuthenticated, isAdmin, isLocalMode, tier, hasFeature, login, logout } = useAuth();
+  const { data: version } = useGetVersion({
+    query: { queryKey: getGetVersionQueryKey(), staleTime: Infinity, retry: false },
+  });
 
   const links = [
     { href: "/", label: "Dashboard", icon: LayoutDashboard },
@@ -95,6 +99,24 @@ export function Layout({ children }: { children: React.ReactNode }) {
             </Button>
           )}
         </div>
+        <div className="px-4 py-2.5 border-t flex items-center justify-between text-[11px] text-muted-foreground">
+          <span className="font-medium">toolr</span>
+          {version?.commitSha ? (
+            <a
+              href={`https://git.kubebase.de/admin/tool-evaluator/commit/${version.commitSha}`}
+              target="_blank"
+              rel="noreferrer"
+              className="font-mono hover:underline"
+              title={version.commitSha}
+            >
+              {version.version && version.version !== "dev"
+                ? version.version
+                : `sha-${version.commitSha.slice(0, 7)}`}
+            </a>
+          ) : version?.version && version.version !== "dev" ? (
+            <span className="font-mono">{version.version}</span>
+          ) : null}
+        </div>
       </aside>
 
       <main className="flex-1 flex flex-col min-w-0">