feat(smart-proxy): add UDP transport support with QUIC/HTTP3 routing and datagram handler relay

ts/proxies/smart-proxy/route-preprocessor.ts

@@ -74,6 +74,11 @@ export class RoutePreprocessor {
       return true;
     }
 
+    // Datagram handler routes always need TS
+    if (route.action.type === 'socket-handler' && route.action.datagramHandler) {
+      return true;
+    }
+
     // Routes with dynamic host/port functions need TS
     if (route.action.targets) {
       for (const target of route.action.targets) {
@@ -92,8 +97,9 @@ export class RoutePreprocessor {
     if (needsTsHandling) {
       // Convert to socket-handler type for Rust (Rust will relay back to TS)
       cleanAction.type = 'socket-handler';
-      // Remove the JS handler (not serializable)
+      // Remove the JS handlers (not serializable)
       delete (cleanAction as any).socketHandler;
+      delete (cleanAction as any).datagramHandler;
     }
 
     // Clean targets - replace functions with static values