(convex) guide overhaul

[alexisintech]

What does this solve?

• We received user feedback that the Convex docs were out of date, and also requests for Next.js instructions.

What changed?

• Updates copy overall to better match Docs voice and to ensure all information is up to date
• Removes screenshots
• Adds Next.js instructions

Fixes DOCS-10110

Checklist

• I have clicked on "Files changed" and performed a thorough self-review
• I have added the "deploy-preview" label and added the preview link(s) to this PR description
• All existing checks pass

[NWylynko]

Imma run through this, I've never used convex before so should be a good test

[NWylynko]

Suggested change

With [Convex](https://www.convex.dev/), you can build a backend with a provided realtime database, file storage, text search, scheduling and more. Paired with Clerk's user authentication and management features, you can build a powerful application with minimal effort. This tutorial will show you how to integrate Clerk into your Convex application. It assumes that you have already integrated one of Clerk's SDKs into your application.

With [Convex](https://www.convex.dev/), you can build a backend with a provided realtime database, file storage, text search, scheduling and more. Paired with Clerk's user authentication and management features, you can build a powerful application with minimal effort. This tutorial will show you how to integrate Clerk into your Convex application. It assumes that you have already integrated one of Clerk's SDKs into your application and integrated Convex.

I don't feel its clear that this guide doesn't cover setting up convex

[alexisintech]

ahh it does say it in the sentence before "This tutorial will show you how to integrate Clerk into your Convex application.", but I can say it twice and have it say "This tutorial will show you how to integrate Clerk into your Convex application. It assumes that you have already integrated one of Clerk's SDKs into your Convex app." if that wasn't clear

[NWylynko]

Yea I get what your saying, I definitely just glossed over 'your Convex application', but yea to me it wasn't clear that I already needed both Clerk and Convex setup, this is simply just wiring them together.

[NWylynko]

Great guide! everything worked as expected, didn't run in to any problems.