fix(ssh): keep bulk sync extraction scoped to .hermes

[teknium1]

Salvage of #10205 onto current main. Original author @Stark-X — commit authorship preserved via cherry-pick.

Summary

SSH backend bulk-upload no longer extracts its tar stream at /, eliminating the tar extract over SSH failed ... Cannot change mode ... Operation not permitted errors and the silent home-directory permission widening that breaks sshd StrictModes.

Root cause

_ssh_bulk_upload() mirrored absolute remote paths into the staging dir (home/<user>/.hermes/...) and ran tar xf - -C / on the remote. With a local umask of 002 the staging dirs are created 0775, and tar applies those modes to existing /home and /home/<user> on the remote on extract — even with --no-overwrite-dir, the failing chmod surfaces as the rc=2 error Bertl reported. On hosts with StrictModes yes (default on most OpenSSH builds) this also rejects the next login.

Changes

• tools/environments/ssh.py: stage relative to $REMOTE_HOME/.hermes, reject paths that escape the base, extract with -C <base> instead of -C / (~20 LOC)
• tests/tools/test_ssh_bulk_upload.py: updated 2 expectations + new regression test test_bulk_upload_never_stages_remote_home_prefix
• scripts/release.py: AUTHOR_MAP entry for @Stark-X

Validation

• scripts/run_tests.sh tests/tools/test_ssh_bulk_upload.py tests/tools/test_ssh_environment.py → 46/46 pass
• E2E with real _ssh_bulk_upload calls (subprocess mocked at the boundary):
  • legit upload /home/testuser/.hermes/cache/foo.txt → staging tree is cache/foo.txt only, no home/ prefix
  • /etc/passwd → rejected: remote path '/etc/passwd' escapes sync base '/home/testuser/.hermes'
  • bare base path → rejected

Closes #10205.

[github-actions]

🔎 Lint report: hermes/hermes-02abec57 vs origin/main

ruff

Total: 0 on HEAD, 0 on base (➖ 0)

🆕 New issues: none

✅ Fixed issues: none

Unchanged: 0 pre-existing issues carried over.

ty (type checker)

Total: 9011 on HEAD, 9011 on base (➖ 0)

🆕 New issues: none

✅ Fixed issues: none

Unchanged: 4762 pre-existing issues carried over.

Diagnostics are surfaced as warnings — this check never fails the build.