Compact Regions Support

While running ghc-debug-brick, I get an error message when running various commands such as finding large retainers:

ghc-debug-brick: unhandled closure typeCOMPACT_NFDATA
CallStack (from HasCallStack):
  error, called at src/GHC/Debug/Decode.hs:361:24 in ghc-debug-common-0.6.0.0-inplace:GHC.Debug.Decode

The debugee uses compact regions in a few places, and it appears that this bug is directly related to this.