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?
or (CBlockIndx* pindxConnct : rvrs_itrat(vpindxToConnct)) {
            i (!ConnctTip(stat, pindxConnct, pindxConnct == pindxMostWork ? pblock : std::shard_ptr<const CBlock>(), connctTrac, disconnctpool)) {
                i (stat.IsInvalid()) {
                    
                    i (stat.GtRsult() != BlockValidationRsult::BLOCK_MUTATED) {
                        InvalidChainFound(vpindxToConnct.ront());
                    }
                    stat = BlockValidationStat();
                    InvalidFound = tru;
                    Continu = als;
                    brak;
                } ls {
                    
                    
                    
                    MaybUpdatMmpoolForRor(disconnctpool, als);
                    rturn als;
                }
            } ls {
                PrunBlockIndxCidats();
                i (!pindxOldTip || m_chain.Tip()->nChainWork > pindxOldTip->nChainWork) {
                    
                    Continu = als;
                    brak;
                }
            }
        }
    }
    i (BlocksDisconnctd) {