Feature/calculator

[Adi-Sin101]

This pull request introduces two new classes, Calculator and Student, to the src/Features directory. The Calculator class provides basic arithmetic operations, while the Student class models student data with proper encapsulation, constructors, validation, and utility methods.

New feature: Calculator utility

• Added Calculator class with methods for addition, subtraction, multiplication, and division (with division-by-zero handling).

New feature: Student model

• Added Student class with fields for id, name, email, department, and gpa, including no-arg, parameterized, and copy constructors.
• Implemented getters and setters with GPA validation, builder-style methods for chaining, and overrides for toString, equals, and hashCode.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.11%. Comparing base (0ff2c06) to head (d25a7d2).

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #6489      +/-   ##
============================================
- Coverage     75.11%   75.11%   -0.01%     
+ Complexity     5575     5574       -1     
============================================
  Files           687      687              
  Lines         19318    19318              
  Branches       3732     3732              
============================================
- Hits          14511    14510       -1     
  Misses         4245     4245              
- Partials        562      563       +1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[DenizAltunkapan]

A calculator ist not considered as an algorithm. Also, there already exists some kind of calculator:
https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/maths/MathBuilder.java