docs: add menu link to API reference

[hamatoyogi]

What is it?

• [x] Feature / enhancement
• [ ] Bug
• [x] Docs / tests / types / typos

Description

Added a link to the API reference

Checklist:

• [x] My code follows the developer guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have made corresponding changes to the documentation
• [ ] Added new tests to cover the fix / functionality

[bolt-new-by-stackblitz[bot]]

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[zanettin]

thx a lot @hamatoyogi ! yes we just added a link here (https://qwik.builder.io/docs/) to it