efcafae810
ssh-gate was built for non-git SSH (PRD 0007), but every upstream currently declared in any bottle is a git remote, and those now flow through git-gate (PRD 0008) with credential isolation, gitleaks scanning, and `insteadOf` URL rewrites. ssh-gate is left doing L4 forwarding with no gating value over git-gate's path; carrying it means a redundant sidecar lifecycle, a shadow-route validator between bottle.ssh and bottle.git, and a third place to keep an SSH identity in sync. Goal is straightforward deletion: bottle.ssh becomes a parse error pointing at bottle.git, the SshEntry / SSHGate / socat provisioner / pipelock allowlist branch all go away, and PRD 0007 carries a "Superseded by PRD 0009" header so the rationale of the prior design stays in the tree.