Implement task tracker CLI with JSON persistence and tests

[Rahulthespy]

Motivation

• Provide a minimal, complete, and runnable CLI-based task tracker with persistent JSON storage so tasks can be added, listed, completed, and deleted from the command line.
• Ship a packaged project layout and automated tests to make the project easy to run and verify with pytest.

Description

• Added src/tracker.py implementing a Task dataclass and TaskTracker with JSON load/save, add_task, list_tasks, complete_task, and delete_task behavior and validation.
• Added src/main.py CLI entrypoint using argparse with add, list, done, and delete subcommands and a configurable --db path, and wired a console script labtracker in pyproject.toml.
• Added pyproject.toml with project metadata, labtracker entry point, and pytest configuration, and added .gitignore for Python artifacts.
• Added unit tests in tests/test_tracker.py covering add/list, complete/delete, invalid task id, and blank-title validation, and updated README.md with quickstart and usage examples.

Testing

• Ran python -m pytest -q which executed the test suite.
• All tests passed: 4 passed (covers add/list, complete/delete, invalid id, and blank title cases).

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Catch TaskTracker validation errors in CLI

TaskTracker raises ValueError for normal user mistakes (e.g., unknown task IDs or blank titles), but this call path is not wrapped in error handling, so common input errors print full Python tracebacks and look like crashes. For example, done on a non-existent ID currently exits with a stack trace instead of a clean CLI error; this should be handled in main() with a user-facing message and non-zero exit.

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