Add a heat flux wrapper#144

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GardevoirX wants to merge 7 commits intometatensor:mainfrom

GardevoirX:heat-flux-wrapper

Commits on Feb 3, 2026

Commits on Feb 4, 2026

Minor
GardevoirX
committed

Commits on Feb 7, 2026

Add `HardyHeatFluxWrapper` for comparison
GardevoirX
committed

Commits on Feb 10, 2026

Fix bugs in non-orthogonal boxes
GardevoirX
committed

Commits on Feb 12, 2026

Update tests
GardevoirX
committed