Add: api schema app

add for generating OpenAPI schema and documentation

backend/api/schema/apps.py

@@ -0,0 +1,6 @@
+from django.apps import AppConfig
+
+
+class ApiConfig(AppConfig):
+    default_auto_field = "django.db.models.BigAutoField"
+    name = "api.schema"

backend/api/schema/urls.py

@@ -0,0 +1,22 @@
+from django.urls import path
+
+from drf_spectacular.views import (
+    SpectacularAPIView,
+    SpectacularRedocView,
+    SpectacularSwaggerView,
+)
+
+urlpatterns = [
+    path("", SpectacularAPIView.as_view(), name="schema"),
+    # Optional UI:
+    path(
+        "swagger-ui/",
+        SpectacularSwaggerView.as_view(url_name="schema"),
+        name="swagger-ui",
+    ),
+    path(
+        "redoc/",
+        SpectacularRedocView.as_view(url_name="schema"),
+        name="redoc",
+    ),
+]