feat: export types to classcharts-api/types

This allow types to be easily accessed without knowing the full path.
Eliminates the need to decide which types should be exported from mod.ts

mod.ts

@@ -1,13 +1,2 @@
 export * from "./src/core/studentClient.ts";
 export * from "./src/core/parentClient.ts";
-export type {
-  ActivityPoint,
-  Announcement,
-  AttendanceDate,
-  Badge,
-  BehaviourTimelinePoint,
-  Detention,
-  Homework,
-  Lesson,
-  Student,
-} from "./src/types.ts";