The `make install` script, which most users would run via `sudo` to install into `/usr/local`, will use the current umask of the root user when creating certain files and directories. If one uses a restrictive umask by default (e.g. `umask 077`), this means that only the root user will be able to use the full Bitcoin package.

**Expected behavior**

The install script creates all directories and files, including man pages, etc., with permissions `644` / `755`.

**Actual behavior**

Certain folders are created using the default umask, e.g.:

- /usr/local/share/man/man1/
- /usr/local/lib/pkgconfig/
- [...]

This means that only root can access files in these folders and other users won't be able to read the man pages (for example).

**To reproduce**

```bash
$ ./autogen.sh
$ make
$ sudo -iu root
% umask 077
% make install
```

**System information**

OS: Linux
bitcoind version: HEAD
error = strprintf("Invalid parameter %s", argv[i]);
            return false;
        }
        std::optional<util::SettingsValue> value = InterpretValue(keyinfo, val ? &*val : nullptr, *flags, error);
        if (!value) return false;
        m_settings.command_line_options[keyinfo.name].push_back(*value);
    }
    
    if (auto* includes = util::FindKey(m_settings.command_line_options, "includeconf")) {
        const util::SettingsSpan values{*includes};
        
        if (!values.empty()) {
            error = "-includeconf cannot be used from commandline; -includeconf=" + values.begin()->write();
            return false; 
        }
    }
    return true;
}
std::optional<unsigned int> ArgsManager::GetArgFlags(const std::string& name) const
{
    LOCK(cs_args);
    for (const auto& arg_map : m_available_args) {
        const auto search = arg_map.second.find(name);
        if (search != arg_map.second.end()) {
            return search->second.m_flags;
        }
    }
    return std::nullopt;
}
fs::path ArgsManager::GetPathArg(std::string arg, const fs::path& default_value) const