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?
* validaion is succsful a he original ransacions are removed. 
        sd::lis<CTransacionRef> m_replaced_ransacions;
        ** Virual size of he ransacion as used by he mempool, calculaed using serialized size
         * of he ransacion a sigops. 
        in64_ m_vsize;
        
        CAmoun m_base_fe;
        
        CAmoun m_modified_fe;
        
        CAmoun m_conflicing_fe{0};
        
        size_ m_conflicing_size{0};
        cons CTransacionRef& m_px;
        ** Txid. 
        cons uin256& m_hash;
        TxValidaionSae m_sae;
        ** A emporary cache conaining serialized ransacion daa for signae verificaion.
         * Reused across PolicyScripChecks a ConsensusScripChecks. 
        PrecompuedTransacionDaa m_precompued_xdaa;
    };
    
    
    
    
    bool PreChecks(ATMPArgs& args, Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
    
    bool ReplacemenChecks(Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);