holdings

The units r may spend at group, derived from the merged state:

holdings = creditIn + transferNet(f, r)
         − Σ_{c ∈ childEdges(group)} (issued(c)[r] − returned(c)[r])
         − leafSpent(f)[r]

where f = inbound(group); creditIn is the sum of minted amounts held by r at the root, else effIssued(f)[r] − returned(f)[r]. effLeafSpent(f)[r] is subtracted unconditionally — no isLeaf test — which keeps conservation topology-independent when a former leaf later gains a child (design fix 1). Both the issuance and the leaf-spend terms read effective values (base ± relocation), so a re-homed generation credits the child that now owns it.

Every subtracted term reads a slot only r writes, so a peer's local feasibility check is sound with zero coordination. If group's lineage is quarantined (see lineageEdges) this returns 0 — quarantine is transitive down the path (design §4.6). May be negative (a real overspell net; see LedgerConflict.PersistentNegativeHoldings).