feat: add essential shell commands - pwd, uptime and clearhistory

[yuvii-b]

Summary

This PR adds three essential command-line utilities to MyCMD that enhance the shell's functionality and user experience.
(Closes: #51)

Commands

• pwd - Prints the current working directory path
• uptime - Displays how long the shell has been running since startup
• clearhistory - Clears the stored command history

Changes Made

• Added PwdCommand.java, UptimeCommand.java, and ClearHistoryCommand.java
• Enhanced ShellContext.java with uptime tracking and history management
• Registered new commands in App.java
• Fixed HelpCommand.java argument parsing bug (was using args[1] instead of args[0])
• Added target/ directory to .gitignore since pushing it just bloats the repo and causes unnecessary merge conflicts.

Usage Examples

mycmd> pwd
C:\Users\user\Projects\mycmd

mycmd> uptime
Up since 0h 12m 45s

mycmd> clearhistory
Command history cleared.

Technical Details

• All commands follow the existing Command interface pattern
• Commands integrate seamlessly with the help system
• No breaking changes to existing functionality
• ShellContext now tracks start time for uptime calculation

Testing

• All commands compile without errors
• Commands appear in help listing with descriptions
• help <command> works for all new commands

[github-actions]

🚀 Hi @yuvii-b!

Thank you for contributing to MyCMD. A maintainer will review your PR shortly. 🎉

[github-actions]

🚀 Hi @yuvii-b!

Thank you for contributing to MyCMD. A maintainer will review your PR shortly. 🎉

[yuvii-b]

This repo was fun to explore! Appreciate how clean and beginner-friendly it is!

[anshumanjadiya1102]

Hello @yuvii-b, I really love your contribution. Do you want to be a part of our Community.

[yuvii-b]

Hello @yuvii-b, I really love your contribution. Do you want to be a part of our Community.

Thanks! I’d love to join. @anshumanjadiya1102

[anshumanjadiya1102]

Hello @yuvii-b, You are invited to our Organization. Now you are a part of Drive-for-Java Community. Thanks for sharing love.