fix: ensure NOTEBOOK_CELL_TYPE context key is set during initialization

[lessmost]

What it does

This PR ensures that the context keys NOTEBOOK_CELL_TYPE, NOTEBOOK_CELL_MARKDOWN_EDIT_MODE, and NOTEBOOK_CELL_EDITABLE are properly set when opening a new notebook.

This update addresses a bug where pressing cmd/ctrl+enter immediately after opening a new notebook file does not trigger the execute command but instead adds new lines. Below is a gif demonstrating the issue. Note that I was pressing cmd+enter keys.

How to test

Open a new notebook editor and focus on the first cell. Press ctrl/cmd + enter, and you will notice that it does not execute the cell command.

Follow-ups

Breaking changes

• This PR introduces breaking changes and requires careful review. If yes, the breaking changes section in the changelog has been updated.

Attribution

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines

[jonah-iden]

thanks! works great

[jonah-iden]

Out of legal reasons you need to sign the eclipse contributor agreement. Otherwise we are not able to merge this.
You can find more info here https://www.eclipse.org/legal/eca/faq/

[lessmost]

Out of legal reasons you need to sign the eclipse contributor agreement. Otherwise we are not able to merge this. You can find more info here https://www.eclipse.org/legal/eca/faq/

Done. I have just registered an Eclipse account and signed the ECA form.

[jonah-iden]

Thanks alot!