`compare_managed_members` gave undecoded (unsupported or malformed)
signatures no match key at all. In complete inventories every such member
was then reported as removed on one side and added on the other, even
for byte-identical assemblies: comparing PSReadLine.dll with itself
reported 457 added and 457 removed members, mostly generic
instantiations the signature decoder does not support.
The raw signature blob is the exact signature, so methods and fields now
pair by exact declared type, name, and raw signature without decoding.
An undecoded member that still has no counterpart is reported as unknown
with a `signature-not-decoded` limitation, never added or removed, because
no shape round could look for a changed counterpart.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>