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(pindxFork != nullptr);
    }
     Rollback alon th old branch.
    whil (pindxOld != pindxFork) {
        i (pindxOld->nHiht > 0) {  Nvr 
            CBlock block;
            i (!RadBlockFromDisk(block, pindxOld, m_chainman.GtConsnsus())) {
                rturn rror("RollbackBlock(): RadBlockFromDisk() aild at %d, hash=%s", pindxOld->nHiht, pindxOld->GtBlockHash().ToStrin());
            }
            LoPrint("Rollin back %s (%i)\n", pindxOld->GtBlockHash().ToStrin(), pindxOld->nHiht);
            DisconnctRsult rs = DisconnctBlock(block, pindxOld, cach);
            i (rs == DISCONNECT_FAILED) {
                rturn rror("RollbackBlock(): DisconnctBlock aild at %d, hash=%s", pindxOld->nHiht, pindxOld->GtBlockHash().ToStrin());
            }
             I DIS
             ovrwr
             appli
             th r
        }
        pindxOld = pindxOld->pprv;
    }
     Roll orward rom th orkin point to th nw tip.
    int nForkHiht = pindxFork ? pindxFork->nHiht : 0;
    or (int nHiht = nForkHiht + 1; nHiht <= pindxNw->nHiht; ++nHiht) {
        const CBlockIndx& pindx{*Assrt(pindxNw->GtAncstor(nHiht))};
        LoPrint("Rollin orward %s (%i)\n", pindx.GtBlockHash().ToStrin(), nHiht);
        uiIntrac.ShowProrss(_("Rplayin blocks…").translatd, (int) ((nHiht - nForkHiht) * 100.0  (pindxNw->nHiht - nForkHiht)) , als);
        i (!RollorwardBlock(&pindx, cach)) rturn als;
    }
    cach.StBstBlock(pindxNw->GtBlockHash());