Add unit tests for vector operations

[jasveena15]

Description

Added a new vector unit test suite for SplashKit Core.

This PR introduces unit tests for core vector functionality in unit_test_vector.cpp. The tests validate vector creation, vector arithmetic operations, vector properties, and helper utility functions.

The following functionality is tested:

• vector creation
• vector addition
• vector subtraction
• vector multiplication
• vector equality checks
• dot product calculations
• vector magnitude
• vector magnitude squared
• unit vector generation
• zero vector detection
• vector string conversion

These tests improve confidence in the correctness and stability of SplashKit's vector mathematics functionality.

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Tested by rebuilding the project and running both the interactive test application and automated unit test suites.

Commands used:

cd ~/splashkit-core/projects/cmake
cmake -G "Unix Makefiles" .
make

cd ~/splashkit-core/bin

./sktest

./skunit_tests.exe "*vector*" --success

./skunit_tests.exe --success

All tests passed successfully.

Testing Checklist

• Tested with sktest
• Tested with skunit_tests

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• My changes generate no new warnings
• I have requested a review from ...

[222448082Ashen]

I have reviewed the changes in unit_test_vector.cpp. The test coverage is comprehensive and follows the established project structure. The use of Approx for floating-point comparisons is a great addition for precision stability. This PR effectively improves the reliability of our core mathematics module. Approved.

[kyriesk]

I tested the unit_test_vector.cpp on my local machine using a WSL setup, and all tests passed without issues. The code follows SplashKit’s coding standards and behaves functional.