fix: prevent 'cd ..' from moving above root directory

[Harushii16]

Summary #35

This PR improves the CdCommand in MyCMD to prevent users from navigating above the root directory. Now, when users execute cd .. at the root, the shell correctly prevents moving further up and shows a clear message.

Changes

• Prevents moving above the root directory.
• Handles relative paths correctly.
• Fully compatible with the existing MyCMD shell.

Notes

• This fix currently supports cd .. (with space).
• The command cd.. (without space) is not affected because the shell does not parse it separately. Supporting it would require changes to the core input parser.

Motivation

Currently, executing cd .. at the root directory could cause unexpected behavior. This fix ensures the shell behaves reliably, preventing potential user errors and improving usability.

Hacktoberfest 2025

This contribution is submitted as part of Hacktoberfest 2025. 🎉
Excited to contribute and improve open-source software!

[Copilot]

Pull Request Overview

This PR fixes the CdCommand to prevent users from navigating above the root directory when using cd .., improving shell reliability and user experience.

• Adds root directory boundary checking to prevent navigation above filesystem root
• Implements special handling for cd .. command with clear user feedback
• Includes workaround for cd.. (without space) command parsing

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[anshumanjadiya1102]

@Harushii16, Please view above suggestions given by Copilot.

[Harushii16]

I have resolved the copilot suggestions.

[anshumanjadiya1102]

OK @Harushii16, I will merge it. And I have also invited you to our Organization. Join to Become a team member.