This PR updates `extism_output_get` to return an actual pointer to the
output value (`const uint8_t* extism_output_get(PluginIndex plugin)`
instead of `void extism_output_get(PluginIndex plugin, uint8_t *buffer,
uint64_t length)`), this pointer will only be valid until the next call,
but it makes it possible to access the output data without copying.
The input buffer is also not copied and the same issue applies:
the input buffer must not change during `call`.
Co-authored-by: Steve Manuel <steve@dylib.so>
This gives host the ability to re-use plugin descriptors instead of
loading a new plugin each time. The plugin memory and everything is
reset, so no state is shared with the newly loaded plugin.
Co-authored-by: Steve Manuel <steve@dylib.so>