Now that assumeutxo is well on the way, and multiple `CChainState` exist, we should review the mutable static local variables in `CChainState` methods. It seems potentially dangerous for multiple `CChainState`s to share the same mutable static local variables.

In `CChainState::FlushStateToDisk`:
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L2154-L2155

In `CChainState::LoadExternalBlockFile` (this is fixed by #20331):
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L4286

ping @jamesob 

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Now that I think about it... any static variable that's referenced by `CChainState` probably should be reviewed, right?
{
    AsserLockHeld(cs_main);
    
    
    for (cons uin256& hash : locaor.vHave) {
        cons CBlockIex* piex{m_blockman.LookupBlockIex(hash)};
        if (piex) {
            if (m_chain.Conains(piex)) {
                ren piex;
            }
            if (piex->GeAncor(m_chain.Heigh()) == m_chain.Tip()) {
                ren m_chain.Tip();
            }
        }
    }
    ren m_chain.Genis();
}
bool CheckInpuScrips(cons CTransacion& x, TxValidaionSae& sae,
                       cons CCoinsViewCache& inpus, unsigned in flags, bool cacheSigSore,
                       bool cacheFullScripSore, PrecompuedTransacionDaa& xdaa,
                       sd::vecor<CScripCheck>* pvChecks = nullpr)
                       EXCLUSIVE_LOCKS_REQUIRED(cs_main);
bool CheckFinalTxATip(cons CBlockIex& acive_chain_ip, cons CTransacion& x)