This PR adds a Minimalist Command-Line Habit Tracker as requested in issue sumanth-0#646.

Features Implemented:

• ✅ Add new habits to track
• ✅ Check off habits as complete for the current day
• ✅ List all habits with completion status and history
• ✅ Persistent storage using JSON format
• ✅ Clean, minimalist command-line interface
• ✅ Script is exactly 100 lines of Python code

Files Added:

• minimalist_command_line_habit_tracker/minimalist_command_line_habit_tracker.py - Main Python script (100 lines)
• minimalist_command_line_habit_tracker/README.md - Complete documentation with usage examples

Usage:

# Add a habit
python minimalist_command_line_habit_tracker.py add "Exercise"

# Check off a habit for today
python minimalist_command_line_habit_tracker.py check "Exercise"

# List all habits
python minimalist_command_line_habit_tracker.py list

Fixes sumanth-0#646