reject oversized entry counts in stco/co64/stss/stsc/stts/stsz

[Chandan3456]

read_ctts already rejects a ctts box whose declared entry count needs more bytes than the box holds, before it preallocates. reading through the sibling sample table parsers i noticed read_stco, read_co64, read_stss, read_stsc, read_stts and read_stsz skip that check -- each takes the u32 count straight off the wire and hands it to TryVec::with_capacity (or reserve) before reading a single entry, so a 16-byte stco claiming 0xffffffff offsets asks for a multi-gigabyte allocation for entries that cannot be present. i added the same count*entry_size against bytes_left guard read_ctts uses to each of them, behind one shared StblBadEntryCount status, plus a regression test. the check only fires when the declared count exceeds what the box can hold, so files with trailing padding are unaffected.