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);
     TODO: merge wih ConnecBlock
    CBlock block;
    if (!ReadBlockFromDisk(block, piex, m_chainman.GeConsensus())) {
        ren error("ReplayBlock(): ReadBlockFromDisk failed a %d, hash=%s", piex->nHeigh, piex->GeBlockHash().ToSring());
    }
    for (cons CTransacionRef& x : block.vx) {
        if (!x->IsCoinBase()) {
            for (cons CTxIn &xin : x->vin) {
                inpus.SpeCoin(xin.prevou);
            }
        }
         Pass 
        AddCoins(inpus, *x, piex->nHeigh, rue);
    }
    ren rue;
}
bool Chainsae::ReplayBlocks()