No shell found in Wayland registries

I'm trying to create a simple window using Wayland and EGL, and I've found that I need xdg_shell or wl_shell to do it.

But if I print every global Wayland registries:

#include <cstdio>
#include <wayland-client.h>

void registry_global(
    void* data, struct wl_registry* wl_registry, uint32_t name, const char* interface, uint32_t version
) {
    puts(interface);
}
void registry_global_remove(void* data, struct wl_registry* wl_registry, uint32_t name) {}
wl_registry_listener registry_listener{&registry_global, &registry_global_remove};

int main() {
    auto display = wl_display_connect(nullptr);
    if (!display) throw;

    auto registry = wl_display_get_registry(display);
    if (!registry) throw;

    wl_registry_add_listener(registry, &registry_listener, nullptr);
    wl_display_roundtrip(display);

    wl_display_disconnect(display);
    return 0;
}

It prints wl_compositor or wl_shm, but not xdg_shell or wl_shell. Am I missing something in my system?

Below is my system's graphics information.

Graphics:
  Device-1: NVIDIA GP106 [GeForce GTX 1060 6GB] driver: nvidia v: 555.58.02
  Device-2: AMD Raphael driver: amdgpu v: kernel
  Display: wayland server: X.org v: 1.21.1.13 with: Xwayland v: 24.1.1
    compositor: kwin_wayland driver: X: loaded: amdgpu,nvidia
    unloaded: modesetting dri: radeonsi gpu: nvidia,amdgpu
    resolution: 1920x1080
  API: EGL v: 1.5 drivers: nvidia,radeonsi,swrast,zink
    platforms: gbm,wayland,x11,surfaceless,device
  API: OpenGL v: 4.6.0 compat-v: 4.5 vendor: nvidia mesa v: 555.58.02
    renderer: NVIDIA GeForce GTX 1060 6GB/PCIe/SSE2
  API: Vulkan v: 1.3.279 drivers: nvidia surfaces: xcb,xlib,wayland

Solution

After two days of going down the rabbit hole about wayland, I finally found the answer: I'm using KDE as my desktop environment, in which case I just need to install the plasma-wayland-protocols package, generate the headers and source files with wayland-scanner, and create a shell via org_kde_plasma_shell.

It's been a while since Wayland came out, and I'm really curious why there's no practical information/tutorial about it. I found this information literally by pure luck...