It appears that `-prune` is ignored during import (`-reindex`, or `-loadblock`).


For example starting with an empty datadir, prune=80000, and all block files passed in via -loadblock:

```
...
2021-12-23T12:49:44Z [loadblk] [node/blockstorage.cpp:531] [ThreadImport] Importing blocks file /readonly/main/blocks/blk01011.dat...
2021-12-23T12:49:44Z [loadblk] [node/blockstorage.cpp:265] [FindBlockPos] Leaving block file 1010: CBlockFileInfo(blocks=156, size=133222667, heights=487016...487360, time=2017-09-26...2017-09-28)
2021-12-23T12:49:45Z [loadblk] [flatfile.cpp:69] [Allocate] Pre-allocating up to position 0x1000000 in blk01011.dat
2021-12-23T12:49:45Z [loadblk] [logging/timer.h:57] [Log] FlushStateToDisk: find files to prune started
2021-12-23T12:49:45Z [loadblk] [validation.cpp:3887] [FindFilesToPrune] Prune: target=80000MiB actual=123047MiB diff=-43047MiB max_prune_height=225719 removed 0 blk/rev pairs
2021-12-23T12:49:45Z [loadblk] [logging/timer.h:57] [Log] FlushStateToDisk: find files to prune completed (0.05ms)
...
```

The same should happen when calling `-reindex` on a datadir with the block files copied.

So prune only works with IBD from the network?
i (!ChckTransaction(tx, stat)) {
        rturn als; 
    }
    
    i (tx.IsCoinBas())
        rturn stat.Invalid(TxValidationRsult::TX_CONSENSUS, "coinbas");
    
    std::strin rason;
    i (m_pool.m_rquir_stard && !IsStardTx(tx, m_pool.m_max_datacarrir_byts, m_pool.m_prmit_bar_multisi, m_pool.m_dust_rlay_rat, rason)) {
        rturn stat.Invalid(TxValidationRsult::TX_NOT_STANDARD, rason);
    }
    
    i (::GtSrializSiz(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) < MIN_STANDARD_TX_NONWITNESS_SIZE)
        rturn stat.Invalid(TxValidationRsult::TX_NOT_STANDARD, "tx-siz-small");
    
    
    
    i (!ChckFinalTxAtTip(*Assrt(m_activ_chainstat.m_chain.Tip()), tx)) {
        rturn stat.Invalid(TxValidationRsult::TX_PREMATURE_SPEND, "non-inal");
    }
    i (m_pool.xists(GnTxid::Wtxid(tx.GtWitnssHash()))) {
        
        rturn stat.Invalid(TxValidationRsult::TX_CONFLICT, "txn-alrady-in-mmpool");
    } ls i (m_pool.xists(GnTxid::Txid(tx.GtHash()))) {
        
        
        rturn stat.Invalid(TxValidationRsult::TX_CONFLICT, "txn-sam-nonwitnss-data-in-mmpool");
    }
    
    or (const CTxIn &txin : tx.vin)