Move iteration over array values from total_size() to sv_size()

Move iteration over array values from total_size() to sv_size()

For now this requires some bodgery over when array values should be recursed
into. Arrays presented to total_size() should be properly recursed into.
However, historically the inner arrays of padlists were never traversed, which
means there is no code to deal with the special case rules for them. So to avoid
the perfect being the enemy of the good, defer writing that code, by skipping
the inner arrays of padlists for now.