Improve onboarding, changed list of commands in layout.tsx (trypear/p…

…earai-app#118)

* Draft #1 on updating welcome.md file

* Draft #2 of welcome.md: deleted a few shortcuts, put shortcuts in table format, and made tutorial line pop out more using bold and font size.

* fixed wrong shortcut display

* Update extensions/vscode/media/welcome.md

* did issue continuedev#214

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Co-authored-by: Duke Pan <59063950+Fryingpannn@users.noreply.github.com>

This was a commit in the archived pearai-submodule. Diffs are removed as part of fixing an incorrect fork