Resolves the storage account a session recording should be written to: the agent's
RecordingStorageProviderID if set, else its AttachmentStorageProviderID (recordings default to the
attachments account), resolved to that provider's first account. Returns null when nothing is
configured — callers treat that as "do not record" (fail-closed).
Resolves the storage account a session recording should be written to: the agent's
RecordingStorageProviderIDif set, else itsAttachmentStorageProviderID(recordings default to the attachments account), resolved to that provider's first account. Returnsnullwhen nothing is configured — callers treat that as "do not record" (fail-closed).