D050 - PFSC does not compress, and that is the format rather than a shortcut

The reader implements zlib, so a writer looked like it needed a compressor. It does not. The block map is a list of absolute offsets, and blocks stored end to end at a fixed stride are a valid map - a reader hands back any block that is already the full block size. LibOrbisPkg's writer says so in its own class comment: it writes the header and "doesn't actually do compression or anything interesting".

Recorded because it was on the blocker list under the wrong description. Compression was never required; it is an option the format permits and nothing here needs.