Barcelona|oct2025-2|Zhenishai Zhanybek|ModuleTools|Sprint4 - #7

Implement CLI tools: cat, ls, and wc

This PR introduces Python implementations of three classic Unix command-line tools: cat, ls, and wc. The goal was to replicate core functionality and behavior for specific use cases, following the project requirements.

Features
cat
Read and print file contents
Support multiple files and wildcard patterns (.txt)
-n flag: number all lines
-b flag: number only non-empty lines
Graceful handling of missing files
ls
List directory contents
-1 flag: display one item per line
-a flag: include hidden files
Support optional directory argument (defaults to current directory)
Sorted output for consistency
wc
Count lines, words, and characters
Support multiple files and wildcard patterns
Flags:
-l: lines only
-w: words only
-c: characters only
Displays totals when multiple files are provided
Implementation details
Used argparse for CLI argument parsing
Used glob to handle wildcard file patterns
Used os module for filesystem operations
Error handling implemented for missing files/directories
Output formatting aligned with expected Unix behavior
Tested commands
cat sample-files/1.txt
cat -n sample-files/.txt
cat -b sample-files/3.txt

ls -1
ls -1 sample-files
ls -1 -a sample-files

wc sample-files/*
wc -l sample-files/3.txt
wc -w sample-files/3.txt
wc -c sample-files/3.txt
wc -l sample-files/*