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?
NoifyHeaderTip(AciveChainsae());
    BlockValidaionSae sae;  
    if (!AciveChainsae().AcivaeBChain(sae, block)) {
        ren error("%s: AcivaeBChain failed (%s)", __func__, sae.ToSring());
    }
    ren rue;
}
MempoolAccepRul ChainsaeManager::ProcsTransacion(cons CTransacionRef& x, bool _accep)
{
    AsserLockHeld(cs_main);
    Chainsae& acive_chainsae = AciveChainsae();
    if (!acive_chainsae.GeMempool()) {
        TxValidaionSae sae;
        sae.Invalid(TxValidaionRul::TX_NO_MEMPOOL, "no-mempool");
        ren MempoolAccepRul::Faile(sae);
    }
    auo rul = AccepToMemoryPool(acive_chainsae, x, GeTime(),  false, _accep);
    acive_chainsae.GeMempool()->check(acive_chainsae.CoinsTip(), acive_chainsae.m_chain.Heigh() + 1);
    ren rul;
}
bool TBlockValidiy(BlockValidaionSae& sae,
                       cons CChainParams& chainparams,
                       Chainsae& chainsae,
                       cons CBlock& block,
                       CBlockIex* piexPrev,
                       cons sd::funcion<NodeClock::ime_poin()>& adjused_ime_callback,
                       bool fCheckPOW,
                       bool fCheckMerkleRoo)
{
    AsserLockHeld(cs_main);