Fix forwarding rule internal API backward compat

This was previously broken if you used a previously valid input with a
protocol (protocols & hosts are now split into different options)

Author: pimterry

src/rules/requests/request-step-impls.ts

@@ -1252,8 +1252,13 @@ export class PassThroughStepImpl extends PassThroughStep {
 
         // Backward compat for old clients:
         if (data.forwarding && !data.transformRequest?.replaceHost) {
+            const [targetHost, setProtocol] = data.forwarding.targetHost.split('://').reverse();
             data.transformRequest ??= {};
-            data.transformRequest.replaceHost = data.forwarding;
+            data.transformRequest.replaceHost = {
+                targetHost,
+                updateHostHeader: data.forwarding.updateHostHeader ?? true
+            };
+            data.transformRequest.setProtocol = setProtocol as 'http' | 'https' | undefined;
         }
 
         return new PassThroughStep({

src/rules/websockets/websocket-step-impls.ts

@@ -450,8 +450,13 @@ export class PassThroughWebSocketStepImpl extends PassThroughWebSocketStep {
     ): any {
         // Backward compat for old clients:
         if (data.forwarding && !data.transformRequest?.replaceHost) {
+            const [targetHost, setProtocol] = data.forwarding.targetHost.split('://').reverse();
             data.transformRequest ??= {};
-            data.transformRequest.replaceHost = data.forwarding;
+            data.transformRequest.replaceHost = {
+                targetHost,
+                updateHostHeader: data.forwarding.updateHostHeader ?? true
+            };
+            data.transformRequest.setProtocol = setProtocol as 'ws' | 'wss' | undefined;
         }
 
         return _.create(this.prototype, {