Creates a workout, assigned to a student (student_id) or as a template when student_id is empty, with its exercises: sets, reps (or a range with reps_max), load, rest, duration for cardio, notes. Exercises are matched to the Trainer Connect library by name so the student sees the demo video (or pass edb_exercise_id from search_exercises). For a weekly program, call it once per day with the same program name and day_of_week. The student is notified, like in the app.