BREAKING_CHANGE(core): remove legacy forwarding module in favor of route-based system

- Removed the forwarding namespace export from main index
- Removed TForwardingType and all forwarding handlers
- Consolidated route helper functions into route-helpers.ts
- All functionality is now available through the route-based system
- Users must migrate from forwarding.* imports to direct route helper imports

ts/forwarding/factory/index.ts

@@ -1,5 +0,0 @@
-/**
- * Forwarding factory implementations
- */
-
-export { ForwardingHandlerFactory } from './forwarding-factory.js';