fix(ui): sync toast theme with app setting

src/App.tsx

@@ -635,7 +635,7 @@ function App() {
         }
       >
         <div
-          className="flex h-full items-center justify-between gap-2 px-6"
+          className="mx-auto flex h-full max-w-[56rem] items-center justify-between gap-2 px-4"
           data-tauri-drag-region
           style={{ WebkitAppRegion: "drag" } as any}
         >
@@ -730,7 +730,7 @@ function App() {
           </div>
 
           <div
-            className="flex items-center gap-2 h-[32px]"
+            className="flex items-center gap-1.5 h-[32px]"
             style={{ WebkitAppRegion: "no-drag" } as any}
           >
             {currentView === "prompts" && (

src/components/ui/sonner.tsx

@@ -1,11 +1,18 @@
 import { Toaster as SonnerToaster } from "sonner";
+import { useTheme } from "@/components/theme-provider";
 
 export function Toaster() {
+  const { theme } = useTheme();
+
+  // 将应用主题映射到 Sonner 的主题
+  // 如果是 "system"，Sonner 会自己处理
+  const sonnerTheme = theme === "system" ? "system" : theme;
+
   return (
     <SonnerToaster
       position="top-center"
       richColors
-      theme="system"
+      theme={sonnerTheme}
       toastOptions={{
         duration: 2000,
         classNames: {