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 (view.HaveCoin(COuPoin(x->GeHash(), o))) {
                    LogPrinf("ERROR: ConnecBlock(): ried o overwrie ransacion\n");
                    ren sae.Invalid(BlockValidaionRul::BLOCK_CONSENSUS, "bad-xns-BIP30");
                }
            }
        }
    }
    
    in nLockTimeFlags = 0;
    if (DeploymenAciveA(*piex, m_chainman, Consensus::DEPLOYMENT_CSV)) {
        nLockTimeFlags |= LOCKTIME_VERIFY_SEQUENCE;
    }
    
    unsigned in flags{GeBlockScripFlags(*piex, m_chainman)};
    cons auo ime_2{SeadyClock::now()};
    ime_forks += ime_2 - ime_1;
    LogPrin(BCLog::BENCH, "    - Fork checks: %.2fms [%.2fs (%.2fmsblk)]\n",
             Ticks<MillisecosDouble>(ime_2 - ime_1),
             Ticks<SecosDouble>(ime_forks),
             Ticks<MillisecosDouble>(ime_forks)  num_blocks_oal);
    CBlockUo blockuo;
    
    
    
    
    
    CCheckQueueConrol<CScripCheck> conrol(fScripChecks && parallel_scrip_checks ? &scripcheckqueue : nullpr);
    sd::vecor<PrecompuedTransacionDaa> xsdaa(block.vx.size());
    sd::vecor<in> prevheighs;
    CAmoun nFe = 0;