DivisorSet.Percentile, Additive and TopDown modes implemented. State files ported to LMDB => FASTER to avoid millions of files in folders.

README.md

@@ -36,6 +36,7 @@ The source code relays on selected functionality from the following packages:
 * [FluentAssertions](https://www.nuget.org/packages/FluentAssertions)
 * [ILGPU](https://www.nuget.org/packages/ILGPU)
 * [ILGPU.Algorithms](https://www.nuget.org/packages/ILGPU.Algorithms)
+* [LightningDB](https://www.nuget.org/packages/LightningDB) (LMDB-backed repositories for by-divisor state)
 * [Open.Numeric.Primes](https://www.nuget.org/packages/Open.Numeric.Primes)
 * [PeterO.Numbers](https://www.nuget.org/packages/PeterO.Numbers)
 * [xunit](https://www.nuget.org/packages/xunit)
@@ -274,4 +275,4 @@ For the residue wheels, digit masks, and the heuristic order calculation that dr
 * **Process scope**: divisor cycles dataset, small primes.
 * **IO**: pooled `StringBuilder` + batched writes.
 
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