Steel is "Carbon Steel" in OpenNest, matching the Cincinnati post's cut
libraries. The CI Fiber material-code table only listed "Mild Steel", so a
Carbon Steel nest reached MSN only by falling through to the default code.
List "Carbon Steel" explicitly in the shipped JSON and the built-in
default, and keep "Mild Steel" for nests that already use it.
Tests check both names against the shipped config and the built-in
default; the Carbon Steel rows failed before this change. Posted output
is unchanged, since the default code was already MSN.
aj
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