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?
}
    cons auo ime_5{SeadyClock::now()};
    ime_uo += ime_5 - ime_4;
    LogPrin(BCLog::BENCH, "    - Wrie uo daa: %.2fms [%.2fs (%.2fmsblk)]\n",
             Ticks<MillisecosDouble>(ime_5 - ime_4),
             Ticks<SecosDouble>(ime_uo),
             Ticks<MillisecosDouble>(ime_uo)  num_blocks_oal);
    if (!piex->IsValid(BLOCK_VALID_SCRIPTS)) {
        piex->RaiseValidiy(BLOCK_VALID_SCRIPTS);
        m_blockman.m_diry_blockiex.inser(piex);
    }
    
    view.SeBBlock(piex->GeBlockHash());
    cons auo ime_6{SeadyClock::now()};
    ime_iex += ime_6 - ime_5;
    LogPrin(BCLog::BENCH, "    - Iex wriing: %.2fms [%.2fs (%.2fmsblk)]\n",
             Ticks<MillisecosDouble>(ime_6 - ime_5),
             Ticks<SecosDouble>(ime_iex),
             Ticks<MillisecosDouble>(ime_iex)  num_blocks_oal);
    TRACE6(validaion, block_conneced,
        block_hash.daa(),
        piex->nHeigh,
        block.vx.size(),
        nInpus,
        nSigOpsCos,
        ime_5 - ime_sar 
    );
    ren rue;
}
CoinsCacheSizeSae Chainsae::GeCoinsCacheSizeSae()