BattleChain Confidence Pools

Description

PoolStates defines a helper for checking whether an Outcome is terminal:

isTerminal is never called anywhere in the codebase. Every terminality check in
ConfidencePool.sol is instead written as a direct comparison against PoolStates.Outcome
members, e.g.:

Confirmed via repo-wide search — isTerminal has zero call sites in src/:

Impact

None functionally — it's internal pure and costs nothing at runtime if unused (the compiler
strips unreferenced internal functions from deployed bytecode). It is purely a maintainability /
code-hygiene issue: an unused helper that duplicates logic already inlined everywhere else is a
latent inconsistency risk. If a future change ever introduces a fifth Outcome value, or if a
future call site starts using isTerminal instead of the inline pattern, the two representations
of "terminal" could silently drift apart from the direct-comparison sites that would need the same
update.

Recommended Mitigation

Either:

1. Remove isTerminal if it's not intended to be used, or

2. Replace the repeated outcome != PoolStates.Outcome.UNRESOLVED checks throughout
   ConfidencePool.sol with PoolStates.isTerminal(outcome) so there is a single source of truth
   for terminality.