Enable operational advertising (and CASE server) in Darwin framework. (…

…#15951)

Operational advertising and a CASE server is needed for at least two things:

1. Subscriptions, so the other side can establish a CASE session if
   there isn't one already.

2. OTA provider server implementation.

Chances are, things using the framework will want at leasts one of
these things, so we just enable unconditionally when bringing up the
Matter stack.

src/darwin/Framework/CHIP/CHIPDeviceController.mm

@@ -183,6 +183,7 @@ - (BOOL)startup:(_Nullable id<CHIPPersistentStorageDelegate>)storageDelegate
         if (_listenPort) {
             params.listenPort = _listenPort;
         }
+        params.enableServerInteractions = true;
 
         // Initialize device attestation verifier
         // TODO: Replace testingRootStore with a AttestationTrustStore that has the necessary official PAA roots available