Fix API URL handling for Docker deployment

- Replace hardcoded localhost URLs with dynamic host detection from request headers
- Supports both development (localhost:3001) and Docker (localhost:9000 -> 3000) environments
- Uses host header to determine correct protocol and port for internal API calls
- Updated execute-dex, validate, and orders APIs to use dynamic baseUrl
- Ensures proper API communication in containerized environments

test-trade-validation.js

@@ -2,6 +2,9 @@
 const testTradeValidation = async () => {
   console.log('🧪 Testing trade validation with fixed amountUSD...')
   
+  // Use port 9000 for Docker or 3001 for local dev
+  const apiUrl = process.env.DOCKER_MODE ? 'http://localhost:9000' : 'http://localhost:3001'
+  
   const tradeData = {
     symbol: 'USDCUSD',
     side: 'BUY', 
@@ -11,10 +14,11 @@ const testTradeValidation = async () => {
     tradingPair: 'USDCUSD/USDC'
   }
   
-  console.log('🚀 Sending test trade:', tradeData)
+  console.log('🚀 Sending test trade to:', apiUrl)
+  console.log('🚀 Trade data:', tradeData)
   
   try {
-    const response = await fetch('http://localhost:3001/api/trading/execute-dex', {
+    const response = await fetch(`${apiUrl}/api/trading/execute-dex`, {
       method: 'POST',
       headers: { 'Content-Type': 'application/json' },
       body: JSON.stringify(tradeData)