One course, declared in full: src/content/<course-slug>.json.
Remarks
lessonCount and moduleCount are deliberately absent. They are derived
from the nesting when the manifest is flattened, so they cannot disagree with
the lessons actually declared. Likewise courseId and moduleId are absent
from the nested rows — position in the tree already says what they are.
One course, declared in full:
src/content/<course-slug>.json.