Dev Portal: VS Code extension reference

## Jobs to be done (optional)
Purpose: if these live in the docs, they might be easier to find and feed Ask AI.

## Definition of done
* Create a reference page with the content from https://marketplace.visualstudio.com/items?itemName=konghq.vscode-konnect-dev-portal-toolkit
* Track down where we link to this and replace that link instead with a link to this reference page

## Information
Request: https://kongstrong.slack.com/archives/CDSTDSG9J/p1785434469576819

## Due date (optional)

## Size
M

Start by reviewing the VS Code extension details at the linked Visual Studio Marketplace page, then search the documentation for links to that marketplace entry. Create a reference page with the marketplace content and replace the existing link(s) with the new page link; done means the reference is available and all identified links point to it.

Written by the indexing model from the issue text.