Vault connection types:

• Not connected (default): disable Vault. No Vault HTTP or Vault Plugin calls. Stack Env[] uses step env only.
• Inherit from System: use the official HashiCorp Vault Plugin System configuration. Soft dependency — install the Vault Plugin for Inherit.
• Manual: self-contained HTTP AppRole on this step (vaultUrl + Username/Password). Vault Plugin is not required.

Path and KV mount are on Inherit/Manual only. Vault wins over step text env on key collisions.