feat: Supply documentation links for course apps from the backend (#28327)

Instead of hard-coding the "Learn More" and potentially other links for course
apps in the course authoring  MFEs this change loads those URLs from the
django settings as part of each individual course app.

openedx/core/djangoapps/course_apps/plugins.py

@@ -23,6 +23,11 @@ class CourseApp(ABC):
     name: str = ""
     # A description for the app.
     description: str = ""
+    # A map of documentation links for the app
+    documentation_links: Dict = {
+        # eg:
+        # "learn_more_configuration": "https://..."
+    }
 
     @classmethod
     @abstractmethod

openedx/core/djangoapps/course_apps/rest_api/v1/views.py

@@ -51,6 +51,7 @@ class CourseAppSerializer(serializers.Serializer):  # pylint: disable=abstract-m
     name = serializers.CharField(read_only=True, help_text="Friendly name of the course app.")
     description = serializers.CharField(read_only=True, help_text="A friendly description of what the course app does.")
     legacy_link = serializers.URLField(required=False, help_text="A link to the course app in the legacy studio view.")
+    documentation_links = serializers.JSONField(required=True)
     allowed_operations = serializers.DictField(
         read_only=True,
         help_text="What all operations are supported by the app.",
@@ -65,6 +66,7 @@ class CourseAppSerializer(serializers.Serializer):  # pylint: disable=abstract-m
             "name": instance.name,
             "description": instance.description,
             "allowed_operations": instance.get_allowed_operations(course_key, request.user),
+            "documentation_links": instance.documentation_links,
         }
         if hasattr(instance, "legacy_link"):
             data["legacy_link"] = request.build_absolute_uri(instance.legacy_link(course_key))

openedx/core/djangoapps/discussions/plugins.py

@@ -3,6 +3,7 @@ Course app configuration for discussions.
 """
 from typing import Dict, Optional
 
+from django.conf import settings
 from django.contrib.auth import get_user_model
 from django.utils.translation import ugettext_noop as _
 from opaque_keys.edx.keys import CourseKey
@@ -21,6 +22,9 @@ class DiscussionCourseApp(CourseApp):
     app_id = "discussion"
     name = _("Discussion")
     description = _("Encourage participation and engagement in your course with discussions.")
+    documentation_links = {
+        "learn_more_configuration": settings.DISCUSSIONS_HELP_URL,
+    }
 
     @classmethod
     def is_available(cls, course_key: CourseKey) -> bool: