Manual /compress built a temporary AIAgent without the originating
platform / stable gateway session key, so an external context engine
ingested the retained transcript tail as source=cli during /compress
and again as the real platform on resume (duplicate cli,telegram rows).
Pass platform=_platform_config_key(source.platform) + the in-scope
gateway_session_key, mirroring the normal gateway turn. Assigned into
runtime_kwargs (single-valued, authoritative) so they neither collide
into a duplicate-kwarg TypeError nor lose to a stale resolver value.
Fixes#50422.
r266-tech
2a04137322