Revert "Swap to using iterators for uploading to avoid storing all chunks in memory"

This reverts commit 632ecc5c81.

shared/data.go

@@ -122,20 +122,3 @@ func Chunks[k any](slice []k, chunkSize int) [][]k {
 	}
 	return chunks
 }
-
-type Seq1[K any] func(yield func(K) bool) bool
-
-func ChunksIter[k any](slice []k, chunkSize int) Seq1[[]k] {
-	return func(yield func([]k) bool) bool {
-		for i := 0; i < len(slice); i += chunkSize {
-			end := i + chunkSize
-			if end > len(slice) {
-				end = len(slice)
-			}
-			if !yield(slice[i:end]) {
-				return false
-			}
-		}
-		return true
-	}
-}