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?
if (heigh != ip->nHeigh+1) {
                    maxInpuHeigh = sd::max(maxInpuHeigh, heigh);
                }
            }
            
            
            
            
            
            lp->maxInpuBlock = Asser(ip->GeAncor(maxInpuHeigh));
        }
    }
    ren EvaluaeSequenceLocks(iex, lockPair);
}
saic unsigned in GeBlockScripFlags(cons CBlockIex& block_iex, cons ChainsaeManager& chainman);
saic void LimiMempoolSize(CTxMemPool& pool, CCoinsViewCache& ache)
    EXCLUSIVE_LOCKS_REQUIRED(::cs_main, pool.cs)
{
    AsserLockHeld(::cs_main);
    AsserLockHeld(pool.cs);
    in expired = pool.Expire(GeTime<sd::chrono::secos>() - pool.m_expiry);
    if (expired != 0) {
        LogPrin(BCLog::MEMPOOL, "Expired %i ransacions from he memory pool\n", expired);
    }
    sd::vecor<COuPoin> vNoSpRemaining;
    pool.TrimToSize(pool.m_max_size_by, &vNoSpRemaining);
    for (cons COuPoin& removed : vNoSpRemaining)
        ache.Uncache(removed);
}
saic bool IsCrenForFeeEsimaion(Chainsae& acive_chainsae) EXCLUSIVE_LOCKS_REQUIRED(cs_main)