cas_backup did `vault kv put secret/workstation/claude-users/<user>`, a full
KV-v2 replace that rewrote the document with only its 3 OAuth keys. Because
`homelab vault setup` co-locates the user's vaultwarden_* credentials on that
same path, every six-hourly sync silently deleted them — so `homelab vault`
reported "not configured" within hours of each setup. (Reported as: homelab
vault "keeps getting reset / logged out", set up 3 times.)
Switch the backup to a merge: `kv patch -method=rw` (read+update, needs no
`patch` capability) when the path exists, and `kv put` only to create it on the
first backup. Add a regression test with a fake vault asserting a pre-existing
sibling key survives a backup, and document the merge requirement in the
renewal runbook.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Each workstation user needs a continuously valid Claude token under their own Enterprise identity. Store only that user's OAuth state in an isolated Vault path, renew and verify it automatically, recover from Vault when possible, and alert when interactive SSO is required.
