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 }
```
{
    return RPCHelpMan{"getblockhash",
                "\nReturns hash of block in best-block-chain at height provided.\n",
                {
                    {"height", RPCArg::Type::NUM, RPCArg::Optional::NO, "The height index"},
                },
                RPCResult{
                    RPCResult::Type::STR_HEX, "", "The block hash"},
                RPCExamples{
                    HelpExampleCli("getblockhash", "1000")
            + HelpExampleRpc("getblockhash", "1000")
                },
        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
{
    ChainstateManager& chainman = EnsureAnyChainman(request.context);
    LOCK(cs_main);
    const CChain& active_chain = chainman.ActiveChain();
    int nHeight = request.params[0].get_int();
    if (nHeight < 0 || nHeight > active_chain.Height())
        throw JSONRPCError(RPC_INVALID_PARAMETER, "Block height out of range");
    CBlockIndex* pblockindex = active_chain[nHeight];
    return pblockindex->GetBlockHash().GetHex();
},
    };
}
static RPCHelpMan getblockheader()