When I run `scantxoutset` via RPC using big range (e.g. 10000) on XPUB, the progress report indicator (`scantxoutset status`) reports 100% at start (while the keys are being derived). This is most probably the result of the previous operation. The progress is only reset to zero when the actual scan starts. I would expect the progress is set to zero before the keys are being derived.

Output of periodic calls to `scantxoutset status` while performing long operation.

```
{ progress: 100 }
{ progress: 100 }
{ progress: 100 }
{ progress: 100 }
{ progress: 100 }
{ progress: 100 }
{ progress: 100 }
{ progress: 100 }
{ progress: 100 }
{ progress: 0 }
{ progress: 3 }
{ progress: 6 }
{ progress: 9 }
{ progress: 12 }
{ progress: 15 }
{ progress: 17 }
{ progress: 20 }
{ progress: 23 }
{ progress: 26 }
{ progress: 29 }
{ progress: 32 }
{ progress: 35 }
{ progress: 37 }
{ progress: 40 }
{ progress: 43 }
{ progress: 46 }
{ progress: 49 }
{ progress: 51 }
{ progress: 54 }
{ progress: 57 }
{ progress: 60 }
{ progress: 63 }
{ progress: 66 }
{ progress: 68 }
{ progress: 71 }
{ progress: 74 }
{ progress: 77 }
{ progress: 80 }
{ progress: 82 }
{ progress: 85 }
{ progress: 88 }
{ progress: 91 }
{ progress: 94 }
{ progress: 97 }
{ progress: 100 }
```
LOCK(::cs_main);
    CChain& active_chain = chainman.ActiveChain();
    if (param.isNum()) {
        const int height{param.get_int()};
        if (height < 0) {
            throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Target block height %d is negative", height));
        }
        const int current_tip{active_chain.Height()};
        if (height > current_tip) {
            throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Target block height %d after current tip %d", height, current_tip));
        }
        return active_chain[height];
    } else {
        const uint256 hash{ParseHashV(param, "hash_or_height")};
        CBlockIndex* pindex = chainman.m_blockman.LookupBlockIndex(hash);
        if (!pindex) {
            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
        }
        return pindex;
    }
}
UniValue blockheaderToJSON(const CBlockIndex* tip, const CBlockIndex* blockindex)