feat: complete PRD verification fixes and deployment readiness

- Add CommonModule to provide/export CampusScope across business modules
- Replace DepartmentsModule imports with CommonModule in 11 modules
- Add missing Class/Tenant repository imports to StudentsModule and SchedulesModule
- Fix service specs with CampusScope, ClassRepository, StudentRepository mocks
- Move better-sqlite3 to optionalDependencies for production Docker builds
- Rewrite Dockerfiles for monorepo root build context
- Update docker-compose.yml service build contexts

apps/server/src/dashboard/dashboard.module.ts

@@ -13,11 +13,11 @@ import { Deposit } from '../entities/deposit.entity';
 import { ClassroomRental } from '../entities/classroom-rental.entity';
 import { ClassTeacher } from '../entities/class-teacher.entity';
 import { DashboardService } from './dashboard.service';
-import { DepartmentsModule } from '../departments/departments.module';
+import { CommonModule } from '../common/common.module';
 import { DashboardController } from './dashboard.controller';
 
 @Module({
-  imports: [TypeOrmModule.forFeature([Room, Student, Occupancy, Bill, RoomExpense, Classroom, ClassSchedule, AttendanceRecord, Class, Deposit, ClassroomRental, ClassTeacher]), DepartmentsModule],
+  imports: [TypeOrmModule.forFeature([Room, Student, Occupancy, Bill, RoomExpense, Classroom, ClassSchedule, AttendanceRecord, Class, Deposit, ClassroomRental, ClassTeacher]), CommonModule],
   controllers: [DashboardController],
   providers: [DashboardService],
 })