MINIFICPP-1147 Implemented.

[am-c-p-p]

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[arpadboda]

Overall it's okay.

Added two comments to make sure the new logic is only triggered for "%%[0-9]+".

I think the treewalker should only be created once as a member of the processor.
As it only needs the dll and the logger, it can be created in init phase.
In this case it could store the unordered map and it doesn't need to be passed by the caller as a reference.

[bakaid]

Tested by enabling "Audit Filtering Platform Connection" both for Success and Failure, and setting CWEL to listen on the Security channel.
It now resolves the "Layer Name" properly.

[arpadboda]

LGTM