docs: more code comments and minor style refactoring

api/TimetableType.cs

@@ -1,9 +1,27 @@
 namespace BonchCalendar;
 
+/// <summary>
+/// Types of timetable documents retrieved from sut.ru API.
+/// </summary>
 public enum TimetableType
 {
+	/// <summary>
+	/// Regular timetable document (Занятия).
+	/// </summary>
 	Classes = 1,
+
+	/// <summary>
+	/// Exams timetable document (Экзаменационная сессия).
+	/// </summary>
 	Exams = 2,
+
+	/// <summary>
+	/// Exams timetable for extramural students document (Сессия для заочников).
+	/// </summary>
 	ExamsForExtramural = 4,
+
+	/// <summary>
+	/// Attestations timetable document (Зачеты).
+	/// </summary>
 	Attestations = 14
 }