Write a file `uuid` in server's data directory that contains random UUID, generated at startup if file does not exist.

It will be used for several purposes:
- to anonymously identify server in Sentry (currently Sentry is unusable);
- (possible future usage) to identify server in ensemble.

@tavplubix comments?
#include <daemon/SentryWriter.h>
#include <Poco/Util/Application.h>
#include <Poco/Util/LayeredConfiguration.h>
#include <common/defines.h>
#include <common/getFQDNOrHostName.h>
#include <common/getMemoryAmount.h>
#include <common/logger_useful.h>
#include <Common/formatReadable.h>
#include <Common/SymbolIndex.h>
#include <Common/StackTrace.h>
#include <Common/getNumberOfPhysicalCPUCores.h>
#if !defined(ARCADIA_BUILD)
#    include "Common/config_version.h"
#    include <Common/config.h>
#endif
#if USE_SENTRY
#    include <sentry.h> 
#    include <stdio.h>
#    include <filesystem>
namespace fs = std::filesystem;
namespace
{
bool initialized = false;
bool anonymize = false;
std::string server_data_path;
void setExtras()