Reads --ssh-signing-key-file when set, decodes the file contents,
resolves the effective signing passphrase, and appends
bootstrap.WithSSHCommitSigning to the bootstrap options. When
--ssh-signing-reuse-private-key is set, reads the transport
--private-key-file, pre-flights it against the subcommand-local
gitArgs.password, and reuses the same bytes + passphrase for signing.
The reuse-path pre-flight lives in this subcommand's RunE because
bootstrapValidate does not have access to the transport password.
Mutual exclusion with --gpg-* and explicit-path key-parse validation
are enforced upstream in bootstrapValidate.
Signed-off-by: Hidde Beydals <hidde@hhh.computer>
Hidde Beydals
d8ae939d79