* fix crash reading past end of memory-mapped model file
DataReaderFromMemory used by mapped model loading was unbounded:
read()/reference() advanced past the mapped region, so a truncated
or corrupt .bin crashed with an access violation inside
ModelBinFromDataReader instead of failing cleanly.
Add a size-aware DataReaderFromMemory ctor that clamps reads and
fails references past the end, use it in the mapped branches of
Net::load_model, and propagate load_model()'s return value which
was previously dropped.
* fix bounded memory reader scans and add loading regressions
* f
* reuse bounded memory reader scan buffer
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Co-authored-by: Dr3ladwyn <Dr3ladwyn@users.noreply.github.com>
Co-authored-by: nihui <nihuini@tencent.com>
Dreladwyn