/usr/include/htslib/cram/ is in libhts-private-dev 1.7-2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/htslib/cram/cram.h
/usr/include/htslib/cram/cram_codecs.h
/usr/include/htslib/cram/cram_decode.h
/usr/include/htslib/cram/cram_encode.h
/usr/include/htslib/cram/cram_index.h
/usr/include/htslib/cram/cram_io.h
/usr/include/htslib/cram/cram_samtools.h
/usr/include/htslib/cram/cram_stats.h
/usr/include/htslib/cram/cram_structs.h
/usr/include/htslib/cram/mFILE.h
/usr/include/htslib/cram/misc.h
/usr/include/htslib/cram/open_trace_file.h
/usr/include/htslib/cram/os.h
/usr/include/htslib/cram/pooled_alloc.h
/usr/include/htslib/cram/rANS_byte.h
/usr/include/htslib/cram/rANS_static.h
/usr/include/htslib/cram/sam_header.h
/usr/include/htslib/cram/string_alloc.h