feat(ui): 实现ACG风格UI改造和动画效果

添加樱花飘落和表情点击特效组件，优化卡片动画和背景模糊效果
更新主题色为粉色并添加动漫风格背景图
引入圆角字体提升可爱风格
新增开发文档记录改造计划

src/components/widget/EmojiCursor.astro

@@ -0,0 +1,34 @@
+<script>
+  function createEmoji(e: MouseEvent) {
+    const emojis = ["🌸", "💖", "✨", "🍬", "🎀", "🍭", "🍡", "🐱", "🍥"];
+    const emoji = document.createElement("div");
+    emoji.innerText = emojis[Math.floor(Math.random() * emojis.length)];
+    emoji.style.position = "fixed";
+    emoji.style.left = e.clientX + "px";
+    emoji.style.top = e.clientY + "px";
+    emoji.style.fontSize = Math.random() * 20 + 10 + "px";
+    emoji.style.pointerEvents = "none";
+    emoji.style.userSelect = "none";
+    emoji.style.zIndex = "9999";
+    emoji.style.transition = "all 1s ease-out";
+    
+    // Initial randomness
+    const x = (Math.random() - 0.5) * 50;
+    const y = (Math.random() - 0.5) * 50;
+    
+    document.body.appendChild(emoji);
+
+    // Animate
+    requestAnimationFrame(() => {
+      emoji.style.transform = `translate(${x}px, ${y - 50}px)`;
+      emoji.style.opacity = "0";
+    });
+
+    // Cleanup
+    setTimeout(() => {
+      emoji.remove();
+    }, 1000);
+  }
+
+  document.addEventListener("click", createEmoji);
+</script>