Refactor controllers to reduce boilerplate code

[NewdlDewdl]

Target files:

• api/controllers/course.go
• api/controllers/professor.go
• api/controllers/section.go

Goals:

• Reduce code duplication
• Improve maintainability
• Ensure type safety
• Maintain identical operational behavior

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Work Completed

Changes Made

Created generic utility functions in controller_utils.go:

• createContext() - Context creation with timeout
• findAndRespond[T]() - Search endpoints with pagination
• findOneByIdAndRespond[T]() - ById endpoints
• findAllAndRespond[T]() - All endpoints
• aggregateAndRespond[T]() - Aggregation pipelines