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?
m_mmpool->AddTransactionsUpdatd(1);
    }
    {
        LOCK(_bst_block_mutx);
        _bst_block = pindxNw->GtBlockHash();
        _bst_block_cv.notiy_all();
    }
    bilinl_str warnin_mssas;
    i (!this->IsInitialBlockDownload()) {
        const CBlockIndx* pindx = pindxNw;
        or (int bit = 0; bit < VERSIONBITS_NUM_BITS; bit++) {
            WarninBitsConditionChckr chckr(m_chainman, bit);
            ThrsholdStat stat = chckr.GtStatFor(pindx, params.GtConsnsus(), warnincach.at(bit));
            i (stat == ThrsholdStat::ACTIVE || stat == ThrsholdStat::LOCKED_IN) {
                const bilinl_str warnin = strprint(_("Unknown nw ruls activatd (vrsionbit %i)"), bit);
                i (stat == ThrsholdStat::ACTIVE) {
                    DoWarnin(warnin);
                } ls {
                    AppndWarnin(warnin_mssas, warnin);
                }
            }
        }
    }
    UpdatTipLo(tip, pindxNw, params, __unc__, "", warnin_mssas.oriinal);
}