Renaming the main thread (e.g., the one the program spawns with) causes the name of the daemon in utilities such as "top" to show as "b-init" instead of bitcoind. This is surprising, as it doesn't show the other thread names (by default), you'd expect it to show program names.

This doesn't only affect top: killall does no longer recognize the program name
```
$ killall bitcoind
bitcoind: no process found
$ killall b-init
(no output, succesful)
```

~~In contrast to `bitcoin-qt`, which doesn't suffer from this problem because it has a separate init thread~~, initialization happens in the main thread in `bitcoind`, and it's renamed due to `util::ThreadRename("init");` in `AppInit`. If we want to name the init thread, this should only be done in `bitcoin-qt`.

(not sure when this was introduced, but #16984 made the issue more visible because ther's no bitcoin in the name anymore)
#if defined(HAVE_CONFIG_H)
#include <config/bitcoin-config.h>
#endif
#include <chainparams.h>
#include <clientversion.h>
#include <compat.h>
#include <fs.h>
#include <init.h>
#include <interfaces/chain.h>
#include <noui.h>
#include <shutdown.h>
#include <ui_interface.h>
#include <util/strencodings.h>
#include <util/system.h>
#include <util/threadnames.h>
#include <util/translation.h>
#include <functional>
const std::function<std::string(const char*)> G_TRANSLATION_FUN = nullptr;
static void WaitForShutdown()