df/table: Sum scaled values to compute the totals

[3v1n0]

In order to show the total row we are summing intermediate values as they
are and eventually scaling them.

Now, while this provides a valid output, it also implies that the total value
that we show is not matching the sum of the previously listed values, since
the sum of scaled values may different from the sum of the original values that
gets eventually scaled.

To be consistent with the output:

• Use a new BytesCell struct to track the bytes values
• Keep a scaled value tracked
• Show the sum of the scaled values as total

Closes: #10436

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing 3v1n0:df-sum-scaling-fix (9e1ab7b) with main (d2bd2d3)}

Summary

✅ 142 untouched benchmarks
⏩ 180 skipped benchmarks¹

Footnotes

1. 180 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[3v1n0]

Ah, I was also looking at the percentage but this seems fine since it's not summing percentages, but it computes it everytime

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/shuf/shuf-reservoir (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/sort/sort-stale-thread-mem (fails in this run but passes in the 'main' branch)

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/tail/retry. tests/tail/retry is passing on 'main'. Maybe you have to rebase?

[cakebaker]

Thanks!