design: upgrade global design of the app

src/App.tsx

@@ -1,8 +1,10 @@
 import { useEffect, useState } from "react";
 import { invoke } from "@tauri-apps/api/core";
 import { getCurrentWindow, LogicalSize } from "@tauri-apps/api/window";
+import { WebviewWindow } from "@tauri-apps/api/webviewWindow";
 import { useStore } from "./store";
 import TitleBar from "./components/TitleBar";
+import ResizeHandles from "./components/ResizeHandles";
 import HomeView from "./components/HomeView";
 import GuideView from "./components/GuideView";
 import SettingsPanel from "./components/SettingsPanel";
@@ -58,7 +60,27 @@ export default function App() {
       }, 500);
     });
 
-    return () => { unlisten.then(f => f()); };
+    const unlistenFocus = win.listen("tauri://focus", async () => {
+      const viewer = await WebviewWindow.getByLabel("image-viewer");
+      if (viewer) {
+        const isMin = await viewer.isMinimized();
+        if (isMin) await viewer.unminimize();
+      }
+    });
+
+    const unlistenBlur = win.listen("tauri://blur", async () => {
+      const isMin = await win.isMinimized();
+      if (isMin) {
+        const viewer = await WebviewWindow.getByLabel("image-viewer");
+        if (viewer) await viewer.minimize();
+      }
+    });
+
+    return () => {
+      unlisten.then(f => f());
+      unlistenFocus.then(f => f());
+      unlistenBlur.then(f => f());
+    };
   }, []);
 
   async function handleInitialSync() {
@@ -68,6 +90,7 @@ export default function App() {
 
   return (
     <div className="app-shell">
+      <ResizeHandles />
       <TitleBar onOpenSettings={() => setShowSettings(s => !s)} />
       <div className="app-body">
         <main className="app-main">