SELECT mi.*, ci.excluded forced every caller to filter tombstone
exclusions in Go over a 69-field row, then a 45-field hand converter
(getCollectionItemsRowToMediaItems) copied it field-by-field into
MediaItems for BuildSections. The query now filters
(ci.excluded IS NOT TRUE) itself and returns sqlc.embed(mi) — callers
consume .MediaItems directly, the Go filter loops die in both
collection-detail ladders (JSON + SSR), and the converter is deleted.
Pins, H1/H3 tests, unit suites green.