Improve documentation of partial solution

[konstin]

Improve the docstrings for the partial solution and rename some fields to be easier to understand.

Thanks to @Eh2406 for providing the context for these fields!

[codspeed-hq]

CodSpeed Performance Report

Merging #294 will degrade performances by 6.53%

_{Comparing konsti/dev/partial-solution-docs (9565eca) with dev (e9170cb)}

Summary

❌ 1 (👁 1) regressions
✅ 5 untouched benchmarks

Benchmarks breakdown

	Benchmark	dev	konsti/dev/partial-solution-docs	Change
👁	sudoku-hard	3.9 ms	4.2 ms	-6.53%

[konstin]

That's a dubious looking perf regression

[zanieb]

"packages with decisions" being "packages with a decided version"?

[mpizenberg]

yes

[zanieb]

changed_this_decision_level looks removed?

[mpizenberg]

That's a dubious looking perf regression

the only two structural changes are a tuple converted to a struct with field names, and another struct which has the order of its fields changed. Could it be byte alignement due to the new fields order?

[konstin]

I can't reproduce this locally, and definitely not in the 6% range:

sudoku-hard             time:   [564.46 µs 564.59 µs 564.72 µs]
                        change: [-0.6899% -0.3674% -0.0552%] (p = 0.02 < 0.05)
                        Change within noise threshold.
Found 9 outliers among 100 measurements (9.00%)
  1 (1.00%) low mild
  8 (8.00%) high severe

[Eh2406]

Could it be byte alignement due to the new fields order?

Unless a structure is marked repr(c) rust is allowed to reorder the fields to best pack alignment. So it would be very odd if changing the definition order led to a significant difference in size. It could affect the order fields are dropped, or the implementation of Hash or Eq. I have seen the order effect Eq in such a way that performance changed, but I don't think that applies here.

Overall I am happy with this change, but leave final decision on wordsmithing questions to @mpizenberg.

[mpizenberg]

It’s a clear improvement in my point of view. Thank you!

[konstin]

Had some trouble rebasing but i think everything is in.