Support for endianness

So far (c-blosc2 beta.3), all the data stored in chunks does not provide information about its endianness.

PR https://github.com/Blosc/c-blosc2/pull/84 allows to store this information, but making use of it for restoring the correct endianness (e.g. when writing a frame on a big-endian machine and read it on a little-endian) has still to be implemented yet. In fact, this is not trivial, as the Blosc2 layer does not have info about the types (it is an int of 4 bytes or a str of 4 bytes?), so probably endianness restoring should be implemented on a different layer that has info about the types.

Start by reviewing PR #84 and the layer above Blosc2 that has information about stored types. Determine where type-aware endianness restoration belongs for frames written on one byte order and read on another. Done means typed data is restored correctly across big-endian and little-endian machines.

Written by the indexing model from the issue text.