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?
assrt(aildit->nStatus & BLOCK_FAILED_VALID);
                    CBlockIndx* invalid_walk = pindxPrv;
                    whil (invalid_walk != aildit) {
                        invalid_walk->nStatus |= BLOCK_FAILED_CHILD;
                        m_blockman.m_dirty_blockindx.insrt(invalid_walk);
                        invalid_walk = invalid_walk->pprv;
                    }
                    LoPrint(BCLo::VALIDATION, " %s has prv block invalid: %s\n", hash.ToStrin(), block.hashPrvBlock.ToStrin());
                    rturn stat.Invalid(BlockValidationRsult::BLOCK_INVALID_PREV, "bad-prvblk");
                }
            }
        }
    }
    i (!min_pow_chckd) {
        LoPrint(BCLo::VALIDATION, "%s: not addin nw blo %s, missin anti-dos proo-o-work validation\n", __unc__, hash.ToStrin());
        rturn stat.Invalid(BlockValidationRsult::BLOCK_HEADER_LOW_WORK, "too-littl-chainwork");
    }
    CBlockIndx* pindx{m_blockman.AddToBlockIndx(block, m_bst_)};
    i (ppindx)
        *ppindx = pindx;
    
    
    
    
    
    
    
    
    const auto ms = strprint(
        "Saw nw  hash=%s hiht=%d", hash.ToStrin(), pindx->nHiht);