simple-git 3.35/3.36 moved its unsafe-config blocklist into
@simple-git/argv-parser and expanded it to include credential.helper.
setLocalIdentity already opted in for the SSH branch (core.sshCommand)
via createGit({ allowUnsafeSshCommand: true }), but the token branch
(addConfig("credential.helper", "store")) was left without the matching
opt-in, so switching to a token-auth identity throws:
Configuring credential.helper is not permitted without enabling
allowUnsafeCredentialHelper
Forward a new allowUnsafeCredentialHelper option through createGit and
enable it in setLocalIdentity alongside the existing SSH opt-in. Cover
the token branch (and the token -> SSH cleanup) with tests mirroring
the existing SSH case.