feat: 为 desktop/server 添加 Tailwind CSS 支持和 Biome 集成

- desktop renderer 接入 @tailwindcss/vite，loading 页面改用 Tailwind 类
- 两个 app 添加 biome.json 继承配置：tailwindDirectives + useSortedClasses

apps/desktop/src/renderer/styles.css

@@ -0,0 +1,49 @@
+@import "tailwindcss";
+
+@theme {
+  --animate-breathe: breathe 8s ease-in-out infinite alternate;
+  --animate-slide: slide 1.4s cubic-bezier(0.4, 0, 0.2, 1) infinite;
+  --animate-appear: appear 1s ease-out 0.2s both;
+  --animate-pulse-subtle: pulse-subtle 3s ease-in-out infinite;
+}
+
+@keyframes breathe {
+  from {
+    transform: scale(0.95);
+    opacity: 0.5;
+  }
+  to {
+    transform: scale(1.05);
+    opacity: 0.8;
+  }
+}
+
+@keyframes slide {
+  0% {
+    transform: translateX(-150%);
+  }
+  100% {
+    transform: translateX(350%);
+  }
+}
+
+@keyframes appear {
+  from {
+    opacity: 0;
+    transform: translateY(10px);
+  }
+  to {
+    opacity: 1;
+    transform: translateY(0);
+  }
+}
+
+@keyframes pulse-subtle {
+  0%,
+  100% {
+    opacity: 0.5;
+  }
+  50% {
+    opacity: 0.8;
+  }
+}