chore: 整理 third-party Dark Reader 目录并移除本地说明文件跟踪

third-party/darkreader/tests/inject/support/echo-client.ts

@@ -0,0 +1,11 @@
+export function getEchoURL(content: string, type = 'text/plain'): string {
+    return `http://localhost:9966/echo?${new URLSearchParams({type, content})}`;
+}
+
+export function getCSSEchoURL(content: string): string {
+    return getEchoURL(content, 'text/css');
+}
+
+export function getJSEchoURL(script: string): string {
+    return getEchoURL(script, 'application/javascript');
+}