Find when each of a set of rules last produced a signal.

Send up to 1000 rule_ids; each comes back with the timestamp of its newest signal
(latest_signal), the organization that received it, and how many signals the rule
produced over the window (total). Every requested id is returned in request order
— a rule that produced nothing has latest_signal: null and total: 0, so silence
is never confused with a dropped id.

Window: lookback_days (default 14, max 30) back from now; meta.range_from /
meta.range_to report the window the answer actually covers. Nothing older than the
window is considered, so latest_signal: null means "not in this window", not
"never".

Freshness and precision: the answer comes from a pre-aggregated daily rollup that
is rebuilt hourly, which is what makes it fast enough to call on every rule list. So
latest_signal is exact to the millisecond but can be up to an hour behind, and
total counts the whole UTC days the window touches rather than the exact instant it
starts. For an exact, up-to-the-second count of one rule, use
GET /rules/{rule_id}/signal-summary.

Organization: the search is scoped to your session organization. A
NEBULOCK_INTERNAL_PORTAL_ORG_ID session instead searches every organization
and reports meta.cross_organization: true — the portal owns global rules but
receives no signals of its own, so a scoped lookup would always answer "never
fired". Note this differs from the retro/run proxies, which swap a portal session
onto the customer portal org.