docs(vscode): Enhance GitHub Copilot tutorial with improved flow, clarity, and student guidance

[arshinsikka]

This PR improves the GitHub Copilot tutorial for VS Code by incorporating student-centric enhancements based on feedback from @damithc and @NorbertLoh in issue #138.

Changes Made:

• Added a short info box at the top explaining the need for GitHub account, 2FA, and student verification before using Copilot.
• Clarified the purpose of different Copilot usage modes (Chat, Inline Chat, and Terminal Prompts) with a short guide section.
• Added a light Troubleshooting tip box at the end to help with common setup issues (e.g., Copilot not showing up or missing panel).

These changes aim to reduce confusion for first-time users, especially students, and improve overall tutorial flow.

Closes #138

[damithc]

@NorbertLoh (and others), for your inputs ...
@arshinsikka14 Add yourself as a contributor (at the bottom of the page)

[arshinsikka]

Thanks for the reminder, Prof! I've added myself as a contributor at the bottom of the tutorial in this PR. Let me know if any further edits are needed @NorbertLoh !

[NorbertLoh]

Overall looks good. Just some minor comments to add.

[NorbertLoh]

Just wondering, /explain, /fix works for all three modes and not just the terminal, I think terminal prompts are useful for terminal commands like building the project and then running it etc.

[NorbertLoh]

This is not bolding correctly in the webpage. Perhaps you would need a new line.

[damithc]

@arshinsikka Waiting for you to resolve comments from @NorbertLoh and resolve conflicts

[arshinsikka]

Hi Prof @damithc,

I’ve completed the requested updates to the VS Code Copilot tutorial:

• Clarified that slash commands (e.g., /explain, /fix) work in Copilot Chat and Inline Chat, not just the terminal; added a concise tip under the terminal section.
• Added myself as contributor
• Added student-focused notes/tips where relevant.
• Resolved merge conflicts

[damithc]

@NorbertLoh Any inputs on the current version?