feat(billing): WIP interface#105079

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mrduncan wants to merge 4 commits intomasterfrom

mrduncan/wip-billing-interfaces

Commits on Dec 16, 2025

Commits on Dec 18, 2025

feat(billing): Iterate slightly on usage tracking
mrduncan
committed

Commits on Dec 20, 2025

feat(billing): Add some very basic working tests
mrduncan
committed