KeptSolve
One kept solve of a tet volume: an entry of `typeData.feaSolve.history` (field-presentation §FVE-11, §FVD-7).
In the namespace construct::model::presentation. Declared in src/libs/libconstruct/construct/model/presentation/SolveHistory.hpp.
Detailed description
The stored form is `{hash, time, setupHash, summary, path, pinned}`. `pinned` is stored only when it is true.