feat(x-engine): smart spotlight cadence — daily when there's news, quiet when there isn't (#374)

CEO verdict on the blind 3-day timer: 'It should default to 1 day and
be more like... smart.' Now: interval defaults to 1 day; the cycle
skips (with logged reasons) while a spotlight draft is still awaiting
the CEO, and stretches to 3x the interval when nothing has shipped
(CHANGELOG sections via the read clone) since the last spotlight
activity — where activity is a materialized draft's seen_at or a
completed exploration's updated_at, deliberately excluding the stale-
cycle janitor's cancels. The HoM gains an explicit skip exit
(propose_feature_spotlight skip=true + reason: completes the
exploration, no draft, no seen-slug, still counts as activity), and
its spawn prompt now carries the seen ledger WITH dates, what shipped
since the last spotlight, and recently rejected drafts with the CEO's
reasons — fresh-but-unspotlighted first. Fail-open on changelog read
errors so a signal outage never starves the engine.

Co-authored-by: Renn F <rennf93@users.noreply.github.com>

agents/prompts/_generated/verbs.md

@@ -231,7 +231,7 @@ real tools live in their agent_sdk drivers, not role_config.
 | `notify_ack` | `notify_ack(notification_id: UUID)` |
 | `read_messages` | `read_messages()` |
 | `read_a2a` | `read_a2a(see do_server)` |
-| `propose_feature_spotlight` | `propose_feature_spotlight(feature_slug: str, feature_title: str, body: str, wants_video: bool = False, video_script: str = '')` |
+| `propose_feature_spotlight` | `propose_feature_spotlight(feature_slug: str = '', feature_title: str = '', body: str = '', wants_video: bool = False, video_script: str = '', skip: bool = False, skip_reason: str = '')` |
 
 ## auditor