feat: implement core backend modules, notification system, and AI agent skill documentation

feat(admin): wire dashboard modules and implement calendar persistence

fix(database): normalize FK column types for refactored schema sync

refactor: resolve circular dependencies and optimize entities for SWC builder

feat(progress): track student material views and persist course completion updates.

Issue #15 #17 #24 #26 Fixed

feat(enrollments): add endpoint for live student enrollment count

feat: add database test script for office hour slots retrieval

feat(ta-dashboard): unlock live TA APIs on existing routes

Merge branch '004-frontend-backend-contracts'

Courses MANAGEMENT AND ASSIGNING DONE

feat(courses): allow administrative course deletion and refine entities

feat: admin API to assign/remove Instructor and TA for course sections

fix(enrollments): refactor period retrieval and service integration

all works except the comment part

added swagger feature and fixed some errors in the "files" feature

Enrollment Feature DONE AND TESTED SUCCESFULLY