MatterTvCastingBridge should probably stop using zzz_generated/darwin bits

[bzbarsky-apple]

zzz_generated/darwin/controller-clusters/zap-generated (added to the include path in examples/tv-casting-app/darwin/MatterTvCastingBridge/MatterTvCastingBridge.xcodeproj/project.pbxproj) contains the following files:

• CHIPClientCallbacks.h -- not actually included in anything involved in MatterTvCastingBridge, I expect
• CHIPClusters.h -- not sure, but can be replaced with non-generated CHIPCluster.h and using ClusterBase
• IMClusterCommandHandler.cpp -- I expect not used in MatterTvCastingBridge, but not sure
• access.h -- Since no server clusters are defined in controller-clusters.zap, this file as it's included now defines no non-default access (i.e. all reads need View, all writes/commands need Operate no matter what attribute/command is involved). If that default access is OK for MatterTvCastingBridge and then it can either use an empty access.h or use a mechanism similar to what Stop using app-specific codegen in Darwin framework builds. #26669 is doing to not even include the file. If the default is not OK, then this needs to be figured out in terms of what actual access policies this is trying to use.
• endpoint_config.h -- There are no server clusters in controller-clusters.zap, so this could just be an empty file.
• gen_config.h -- I really doubt anything from here is used in MatterTvCastingBridge; could just be an empty file.

[bzbarsky-apple]

@lazarkov @chrisdecenzo