add update service

frontend/public/favicon.svg

@@ -8,7 +8,7 @@
    version="1.1"
    id="svg1"
    inkscape:version="1.4.3 (0d15f75, 2025-12-25)"
-   sodipodi:docname="argonode.svg"
+   sodipodi:docname="favicon.svg"
    inkscape:export-filename="tono.png"
    inkscape:export-xdpi="130.05"
    inkscape:export-ydpi="130.05"
@@ -49,28 +49,17 @@
        height="194.43169"
        x="2.5203834"
        y="2.9819231"
-       rx="52.916668"
-       ry="52.916668" />
+       rx="97.484589"
+       ry="97.215843" />
     <path
-       style="fill:#ffffff;fill-opacity:1;stroke:#ffffff;stroke-width:8.251;stroke-linecap:round;stroke-linejoin:round;stroke-dasharray:none;stroke-opacity:1"
-       d="m 80.438549,119.47945 85.556771,-87.012984 4.46561,16.665896 -16.7032,-4.47561"
+       style="fill:#ffffff;fill-opacity:1;stroke:#ffffff;stroke-width:9.87521;stroke-linecap:round;stroke-linejoin:round;stroke-dasharray:none;stroke-opacity:1"
+       d="M 62.915486,149.85992 165.31436,45.718188 l 5.34467,19.946625 -19.99127,-5.356646"
        id="path6"
        sodipodi:nodetypes="cccc" />
     <path
-       style="fill:#ffffff;fill-opacity:1;stroke:#ffffff;stroke-width:3.95096;stroke-linecap:round;stroke-linejoin:round;stroke-dasharray:none;stroke-opacity:1"
-       d="M 133.7656,68.457841 H 103.74962 L 50.836303,122.45621 80.512342,121.94367"
+       style="fill:#ffffff;fill-opacity:1;stroke:#ffffff;stroke-width:4.72872;stroke-linecap:round;stroke-linejoin:round;stroke-dasharray:none;stroke-opacity:1"
+       d="M 126.74012,88.794566 H 90.815406 l -63.329451,64.628104 35.51785,-0.61344"
        id="path7"
        sodipodi:nodetypes="cccc" />
-    <text
-       xml:space="preserve"
-       style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:80px;line-height:0;font-family:Futura;-inkscape-font-specification:'Futura, Normal';font-variant-ligatures:normal;font-variant-caps:normal;font-variant-numeric:normal;font-variant-east-asian:normal;writing-mode:lr-tb;direction:ltr;fill:#ffffff;fill-opacity:1;stroke:#ffffff;stroke-width:2.75827;stroke-linecap:round;stroke-linejoin:round;stroke-dasharray:none;stroke-opacity:1"
-       x="18.009901"
-       y="172.8485"
-       id="text8"><tspan
-         sodipodi:role="line"
-         id="tspan8"
-         style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;font-size:80px;font-family:Futura;-inkscape-font-specification:'Futura, Normal';font-variant-ligatures:normal;font-variant-caps:normal;font-variant-numeric:normal;font-variant-east-asian:normal;stroke-width:2.75827;stroke-dasharray:none"
-         x="18.009901"
-         y="172.8485">tono</tspan></text>
   </g>
 </svg>

frontend/src/App.tsx

@@ -897,6 +897,7 @@ function Flow() {
   const [executingNodeId, setExecutingNodeId] = useState<string | null>(null);
   const [helpTabs, setHelpTabs] = useState<{ label: string; type?: string; content: string | null }[]>([]);
   const [activeHelpTab, setActiveHelpTab] = useState<string | null>(null);
+  const [updateInfo, setUpdateInfo] = useState<{ latest: string; url: string } | null>(null);
 
   const flowContainerRef = useRef<HTMLDivElement | null>(null);
   const panTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
@@ -918,6 +919,19 @@ function Flow() {
   const reactFlow = useReactFlow<TonoNode, TonoEdge>() as ReturnType<typeof useReactFlow<TonoNode, TonoEdge>> & { updateNodeInternals: (id: string) => void };
   const undoRedo = useUndoRedo();
 
+  // ── Update check (native builds only) ──────────────────────────────
+  useEffect(() => {
+    if (!(window as any).pywebview) return;
+    fetch('/check-update')
+      .then((r) => r.ok ? r.json() : null)
+      .then((data) => {
+        if (data?.update_available && data.latest) {
+          setUpdateInfo({ latest: data.latest, url: data.url });
+        }
+      })
+      .catch(() => {});
+  }, []);
+
   const scheduleAutoRun = useCallback(() => {
     if (autoRunTimer.current) clearTimeout(autoRunTimer.current);
     autoRunTimer.current = setTimeout(() => autoRunRef.current?.(), 300);
@@ -3179,6 +3193,15 @@ function Flow() {
           <div className={`status-bar ${status.level}`}>{status.text}</div>
         </div>
 
+        {updateInfo && (
+          <div className="update-banner">
+            tono {updateInfo.latest} is available.
+            {' '}
+            <a href={updateInfo.url} target="_blank" rel="noopener noreferrer">Download</a>
+            <button className="update-banner-dismiss" onClick={() => setUpdateInfo(null)} title="Dismiss">✕</button>
+          </div>
+        )}
+
         {/* React Flow canvas */}
         <div
           ref={flowContainerRef}

frontend/src/styles.css

@@ -212,6 +212,34 @@ html, body, #root {
 .status-bar.info  { color: var(--accent-light); }
 .status-bar.error { color: var(--error-text); background: var(--error-bg); }
 
+.update-banner {
+  background: var(--accent);
+  color: #fff;
+  text-align: center;
+  padding: 4px 12px;
+  font-size: 12px;
+  position: relative;
+}
+.update-banner a {
+  color: #fff;
+  font-weight: 600;
+  text-decoration: underline;
+}
+.update-banner-dismiss {
+  position: absolute;
+  right: 8px;
+  top: 50%;
+  transform: translateY(-50%);
+  background: none;
+  border: none;
+  color: #fff;
+  cursor: pointer;
+  font-size: 13px;
+  padding: 2px 4px;
+  opacity: 0.7;
+}
+.update-banner-dismiss:hover { opacity: 1; }
+
 /* ── React Flow container ──────────────────────────────────────────── */
 .flow-container {
   flex: 1;

frontend/vite.config.js

@@ -22,6 +22,7 @@ export default defineConfig({
       '/file-content': 'http://127.0.0.1:8188',
       '/help-docs': { target: 'http://127.0.0.1:8188', changeOrigin: true },
       '/prompt': 'http://127.0.0.1:8188',
+      '/check-update': 'http://127.0.0.1:8188',
       '/ws': {
         target: 'http://127.0.0.1:8188',
         ws: true,