A second repository's trunk defining a seat another trunk holds is refused and kept nowhere, with the finding seat-defined-twice naming both repositories; indexer_seat_definitions_again for a pull request reads the head's own generated-from, so a pull request changing that field is read right by hand too (the lead's rulings on A2i 3 and 4). Claude-Session: https://claude.ai/code/session_01JG73KJNrH5EgFXMKKYSrig