refactor(mascot): replace ChibiMascot SVG with MascotImage PNG and simplify empty states

services/frontend/src/widgets/Sidebar.tsx

@@ -2,7 +2,7 @@ import { motion } from "framer-motion";
 import { BarChart3, MessageSquare, Radio } from "lucide-react";
 import type { DashboardTab } from "../entities/ui/types";
 import { cn } from "../shared/lib/utils";
-import { ChibiMascot } from "./mascot/ChibiMascot";
+import { MascotImage } from "./mascot/MascotImage";
 
 const navItems: Array<{ id: DashboardTab; label: string; icon: typeof Radio }> =
   [
@@ -84,9 +84,9 @@ export function Sidebar({
       {/* Spacer pushes mascot to bottom */}
       <div className="flex-1" />
 
-      {/* Chibi mascot */}
+      {/* Mascot PNG */}
       <div className="flex justify-center pb-4">
-        <ChibiMascot size="sm" variant="idle" />
+        <MascotImage size="sm" />
       </div>
     </motion.nav>
   );

services/frontend/src/widgets/mascot/MascotImage.tsx

@@ -0,0 +1,40 @@
+/**
+ * MascotImage — Anime mascot PNG from GitHub CDN
+ * Replaces ChibiMascot SVG component with external PNG asset
+ */
+
+interface MascotImageProps {
+  size?: "sm" | "md" | "lg";
+  className?: string;
+}
+
+const sizeMap = {
+  sm: "w-16 h-auto",
+  md: "w-32 h-auto",
+  lg: "w-48 h-auto",
+};
+
+export function MascotImage({ size = "md", className = "" }: MascotImageProps) {
+  const sizeClass = sizeMap[size];
+
+  return (
+    <img
+      src="https://raw.githubusercontent.com/IMPHNEN/imphnen-frontend-service/develop/apps/dimentorin/public/image/mascot-1.png"
+      alt="Mascot"
+      className={`object-contain drop-shadow-md ${sizeClass} ${className}`}
+    />
+  );
+}
+
+/**
+ * EmptyStateMascot — Mascot for empty states
+ * Replaces ChibiMascot when showing empty data states
+ */
+export function EmptyStateMascot() {
+  return (
+    <div className="flex flex-col items-center justify-center gap-4 py-12">
+      <MascotImage size="md" className="opacity-60" />
+      <p className="text-sm text-muted-foreground">No data to display</p>
+    </div>
+  );
+}