Add a `pre_verify` user/plugin/shell hook fired once per turn when the agent
edited code and is about to finish, after the existing verify-on-stop guard. A
hook can keep the agent going one more turn (run a check, defer it, tidy the
diff) by returning {"action":"continue","message":...} (the Claude-Code Stop
shape {"decision":"block","reason":...} is accepted too). Hooks receive coding,
attempt, final_response, and sorted changed_paths so they can self-scope and
self-throttle; the path is bounded by agent.max_verify_nudges and preserves
message-role alternation.
Hermes still ships its default coding guidance (agent.verify_guidance, on by
default), but it now rides the evidence-based verify-on-stop missing-evidence
nudge instead of a separate default pre_verify continuation, so it costs no
extra model turn of its own. Guidance reuses the shared utils.is_truthy_value
parser rather than a local copy.
