Updates dog motivation image

WHAT: Replaces the placeholder dog image with an actual image of a dog.
WHY: To provide a more visually appealing and engaging experience for the user. The placeholder was generic and didn't effectively convey the intended motivation.
HOW: Imports the dog image and renders it within the `DogMotivation` component, replacing the previous emoji.

src/features/purchase/components/DogMotivation.tsx

@@ -1,4 +1,5 @@
 import { Card, CardContent } from "@/components/ui/card";
+import dogImageUrl from "../../../../IMG_6702.JPG";
 
 export function DogMotivation() {
   return (
@@ -15,9 +16,9 @@ export function DogMotivation() {
       <Card className="border border-slate-200 shadow-sm relative z-10 bg-white/80 backdrop-blur-sm">
         <CardContent className="p-4">
           <div className="flex items-center gap-4">
-            {/* Original image in proper size */}
+            {/* Render dog image from project root */}
             <div className="shrink-0 w-32 h-32 overflow-hidden rounded-md border border-slate-200 shadow-sm flex items-center justify-center bg-white">
-              <span className="text-5xl" role="img" aria-label="dog">🐶</span>
+              <img src={dogImageUrl} alt="打石膏的小狗" className="w-full h-full object-cover" />
             </div>
             
             <div className="flex flex-col">