Pure --mcp-list never reads secrets (only --mcp-add does), yet the mcp
action path always ran strict Vault::init, so a virgin environment with
no password file exited 1 instead of printing the empty listing. Route
the mcp_inspect path through the established Vault::init_lenient
constructor; get/remove/add stay on the strict init.
Make tests/inspection_flags.rs hermetic against host state: every
spawned binary gets a fresh fake HOME (and USERPROFILE) so a real
~/.coyote_password can't mask virgin-environment regressions, scrubs
IS_SANDBOX/COYOTE_PROVIDER/COYOTE_PLATFORM outside the sandbox-mode
tests, and pins CWD so workspace mcp.json discovery can't leak in.
New tests pin both sides of the boundary: the lenient list path (empty
and configured, never bootstrapping a password file) and the strict
vault gate for get/remove/add.