* fix(cron): pass heartbeat target=last for main-session cron jobs
When a cron job with sessionTarget=main and wakeMode=now fires, it
triggers a heartbeat via runHeartbeatOnce. Since e2362d35 changed the
default heartbeat target from "last" to "none", these cron-triggered
heartbeats silently discard their responses instead of delivering them
to the last active channel (e.g. Telegram).
Fix: pass heartbeat: { target: "last" } from the cron timer to
runHeartbeatOnce for main-session jobs, and wire the override through
the gateway cron service builder. This restores delivery for
sessionTarget=main cron jobs without reverting the intentional default
change for regular heartbeats.
Regression introduced in: e2362d35 (2026-02-25)
Fixes#28508
* Cron: align server-cron wake routing expectations for main-target jobs
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Co-authored-by: Tak Hoffman <781889+Takhoffman@users.noreply.github.com>
