Radarr and Sonarr can return HTTP 201 with no body when a movie or
series is added. The previous code returned an "accepted_without_response"
result with an empty ExternalID, which trapped the reconciler: every
subsequent CheckStatus call short-circuited on the empty ID and the
request never advanced past queued.
When the add POST decodes empty, look the freshly-added record up by
TMDB or TVDB ID via the standard list endpoints and use the resulting
Arr ID. Fall back to the previous accepted-without-response result
only when the lookup also returns no match, preserving the original
behavior as a safety net.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
