feat: 更新嵌入式文件系统逻辑，支持路径清理和静态资源请求处理，增强前端主题切换能力

atsf_server/web/app/globals.css

@@ -6,18 +6,27 @@
 }
 
 html {
+  background: var(--surface-canvas);
+}
+
+html[data-theme='light'] {
+  color-scheme: light;
+}
+
+html[data-theme='dark'] {
   color-scheme: dark;
 }
 
 body {
   min-height: 100vh;
-  background:
-    radial-gradient(circle at top, rgba(56, 189, 248, 0.08), transparent 30%),
-    linear-gradient(180deg, rgba(8, 17, 31, 0.98), rgba(8, 17, 31, 1));
+  background: var(--body-background);
   color: var(--foreground-primary);
   font-family:
     Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI',
     sans-serif;
+  transition:
+    background 0.2s ease,
+    color 0.2s ease;
 }
 
 a {
@@ -30,6 +39,6 @@ button {
 }
 
 ::selection {
-  background: rgba(56, 189, 248, 0.32);
-  color: #f8fafc;
+  background: var(--selection-background);
+  color: var(--selection-foreground);
 }