NeoFS network dictates the limitation of the maximum size of the "finished"
objects. The payload size of an object is recorded in its header. When
writing finished objects, the nodes must check:
* satisfying the constraint;
* matching the value in the header to the number of payload bytes.
Provide value returned by `MaxSizeSource` component to `validatingTarget`.
Check max size value during the stream of the "finished" objects. Check
header value during the streaming and on-close. Check payload size in v2
relay scenario.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>