Review v2 of #93084: the readable-cmdline path used substring matching
as destructive authority. That fails open on prefix collisions
(--profile timothy vs our profile tim) and same-name profiles under
different roots, so a poisoned record could still reach SIGTERM.
Ownership is now decided by the persisted identity record ALONE — exact
_same_hermes_home equality, bound to the live target by exact pid +
start-time. Missing/legacy/unbound/foreign records all refuse. A
readable argv feeds only a token-exact consistency check
(_looks_like_profile_conflict_from_cmdline via shlex tokens) that
refuses explicit contradictions like --profile timothy under tim; bare
or matching argv adds nothing.
Also fixes the review's source-of-record concern: the guard validates
the record that authorizes get_running_pid()'s answer rather than
assuming {HERMES_HOME}/gateway.pid is always the source.
Adds the requested signal-boundary regression: start_gateway(replace=
True) with unprovable ownership returns False without calling
terminate_pid or writing a takeover marker; the bound same-home
counterpart still reaches the replace flow. Legacy replace-flow tests
updated to stage a valid bound record for their legitimate-replace
fixtures.
BrunoBza