feat(x402): Added dexter facilitator implementation

.env-example

@@ -40,7 +40,7 @@ export PRIMARY_FACILITATOR=cdp
 
 # Facilitator URLs
 # For Coinbase CDP (recommended): https://api.cdp.coinbase.com/platform/v2/x402
-# For Dexter (no API keys): https://dexter.cash/facilitator
+# For Dexter (no API keys):https://x402.dexter.cash
 export x402_FACILITATOR_URL=https://api.cdp.coinbase.com/platform/v2/x402
 
 # CDP API Credentials (required when using CDP facilitator)

src/config/env/common.js

@@ -43,6 +43,7 @@ const x402Defaults = {
   serverAddress: process.env.SERVER_BASE_ADDRESS || 'bitcoincash:qqsrke9lh257tqen99dkyy2emh4uty0vky9y0z0lsr',
   facilitatorKeyId: process.env.FACILITATOR_KEY_ID || '',
   facilitatorSecretKey: process.env.FACILITATOR_SECRET_KEY || '',
+  primaryFacilitator: process.env.PRIMARY_FACILITATOR || 'cdp',
   // CDP requires CAIP-2 network format: eip155:8453 (base) or eip155:84532 (base-sepolia)
   network: x402Network,
   priceUSDC

src/config/x402.js

@@ -17,7 +17,7 @@ const FACILITATORS = {
   },
   dexter: {
     name: 'Dexter',
-    url: 'https://dexter.cash/facilitator',
+    url: 'https://x402.dexter.cash',
     requiresAuth: false,
     authType: 'none'
   }