Initial commit: OpenAI compatible API proxy with auto token refresh

- Implemented OpenAI compatible API proxy server
- Support for Anthropic and custom OpenAI format conversion
- Automatic API key refresh with WorkOS OAuth
- SSE streaming response transformation
- Smart header management for Factory endpoints
- Chinese documentation

logger.js

@@ -0,0 +1,60 @@
+import { isDevMode } from './config.js';
+
+export function logInfo(message, data = null) {
+  console.log(`[INFO] ${message}`);
+  if (data && isDevMode()) {
+    console.log(JSON.stringify(data, null, 2));
+  }
+}
+
+export function logDebug(message, data = null) {
+  if (isDevMode()) {
+    console.log(`[DEBUG] ${message}`);
+    if (data) {
+      console.log(JSON.stringify(data, null, 2));
+    }
+  }
+}
+
+export function logError(message, error = null) {
+  console.error(`[ERROR] ${message}`);
+  if (error) {
+    if (isDevMode()) {
+      console.error(error);
+    } else {
+      console.error(error.message || error);
+    }
+  }
+}
+
+export function logRequest(method, url, headers = null, body = null) {
+  if (isDevMode()) {
+    console.log(`\n${'='.repeat(80)}`);
+    console.log(`[REQUEST] ${method} ${url}`);
+    if (headers) {
+      console.log('[HEADERS]', JSON.stringify(headers, null, 2));
+    }
+    if (body) {
+      console.log('[BODY]', JSON.stringify(body, null, 2));
+    }
+    console.log('='.repeat(80) + '\n');
+  } else {
+    console.log(`[REQUEST] ${method} ${url}`);
+  }
+}
+
+export function logResponse(status, headers = null, body = null) {
+  if (isDevMode()) {
+    console.log(`\n${'-'.repeat(80)}`);
+    console.log(`[RESPONSE] Status: ${status}`);
+    if (headers) {
+      console.log('[HEADERS]', JSON.stringify(headers, null, 2));
+    }
+    if (body) {
+      console.log('[BODY]', JSON.stringify(body, null, 2));
+    }
+    console.log('-'.repeat(80) + '\n');
+  } else {
+    console.log(`[RESPONSE] Status: ${status}`);
+  }
+}