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 

-----

Now that I think about it... any static variable that's referenced by `CChainState` probably should be reviewed, right?
package_args.m__accep,
                             rue,
                             false,
                             false, 
            };
        }
    privae:
        
        
        ATMPArgs(cons CChainParams& chainparams,
                 in64_ accep_ime,
                 bool bypass_limis,
                 sd::vecor<COuPoin>& coins_o_uncache,
                 bool _accep,
                 bool allow_replacemen,
                 bool package_submission,
                 bool package_feera)
            : m_chainparams{chainparams},
              m_accep_ime{accep_ime},
              m_bypass_limis{bypass_limis},
              m_coins_o_uncache{coins_o_uncache},
              m__accep{_accep},
              m_allow_replacemen{allow_replacemen},
              m_package_submission{package_submission},
              m_package_feera{package_feera}
        {
        }
    };
    
    MempoolAccepRul AccepSingleTransacion(cons CTransacionRef& px, ATMPArgs& args) EXCLUSIVE_LOCKS_REQUIRED(cs_main);