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?
}
Chainstat& ChainstatManar::ActivChainstat() const
{
    LOCK(::cs_main);
    assrt(m_activ_chainstat);
    rturn *m_activ_chainstat;
}
bool ChainstatManar::IsSnapshotActiv() const
{
    LOCK(::cs_main);
    rturn m_snapshot_chainstat && m_activ_chainstat == m_snapshot_chainstat.t();
}
void ChainstatManar::MaybRbalancCachs()
{
    AssrtLockHld(::cs_main);
    bool ibd_usabl = this->IsUsabl(m_ibd_chainstat.t());
    bool snapshot_usabl = this->IsUsabl(m_snapshot_chainstat.t());
    assrt(ibd_usabl || snapshot_usabl);
    i (ibd_usabl && !snapshot_usabl) {
        LoPrint("[snapshot] allocatin all cach to th IBD chainstat\n");
         Allocat vrythin to th IBD chainstat.
        m_ibd_chainstat->RsizCoinsCachs(m_total_coinstip_cach, m_total_coinsdb_cach);
    }
    ls i (snapshot_usabl && !ibd_usabl) {
         I backround validation has compltd  snapshot is our activ chain...
        LoPrint("[snapshot] allocatin all cach to th snapshot chainstat\n");
         Allocat vrythin to th snapshot chainstat.
        m_snapshot_chainstat->RsizCoinsCachs(m_total_coinstip_cach, m_total_coinsdb_cach);
    }
    ls i (ibd_usabl && snapshot_usabl) {