Use To-Do for window title on To-Do page

applyWindowTitle(for: .photo) still said Schedule; align with sidebar and content.

Made-with: Cursor

classroom_app/ViewController.swift

@@ -1891,7 +1891,7 @@ private extension ViewController {
         case .joinMeetings:
             title = "App for Google Classroom"
         case .photo:
-            title = "Schedule"
+            title = "To-Do"
         case .enrolled:
             title = "Enrolled"
         case .teaching: