v0.1

Add unit tests for Parser, TaskList, and Storage

Added JUnit tests for Parser, TaskList, and Storage to ensure correct behavior.

- ParserTest: Verifies that parsing "todo" and "deadline" commands returns the correct command objects and handles invalid input properly.
- StorageTest: Ensures tasks are saved to and loaded from a file correctly.
- TaskListTest: Checks adding and deleting tasks, including handling invalid deletions.

These tests improve code reliability and facilitate future refactoring.

Let's:
- Continue to regularly update test cases and implement future test cases for future functionalities (stretch goal)