Week 1 v2: Clerk v7 / Core 3 breaks SignedIn, SignedOut, and Protect

[osencan]

Summary

If you install the latest Clerk (@clerk/nextjs v7) instead of pinning 6.39.0, the Day 3 / Day 4 samples crash. Core 3 removed <SignedIn>, <SignedOut>, and <Protect>. They still export, so the build succeeds, then they throw at render:

Clerk: <SignedOut> is not available in @clerk/nextjs Core 3.
Clerk: <Protect> is not available in @clerk/nextjs Core 3.

The official replacement is , but that is a server control. Week 1 pages are "use client", so does not see the browser session.

v2 samples use useAuth() on those client pages:

signed-in vs signed-out → isLoaded && isSignedIn
plan gate → has?.({ plan: 'premium_subscription' }) (do not mount the product until that is true)
Also added a Cursor skill for students who already built Week 1 on v6 and want to convert their app: copy community_contributions/clerk-core3-auth/ to .cursor/skills/clerk-core3-auth/ in your SaaS repo.

Added v2 versions of the week1/day3,4,5 and left the original Week 1 files alone so they still match the current videos.

Files:

• week1/day3_v2.md
• week1/day3.part2_v2.md
• week1/day4_v2.md
• week1/day5_v2.md / prior_day5_app_runner_v2.md (pointer only)
• community_contributions/clerk_core3_signedin_signedout.md
• community_contributions/clerk-core3-auth/ (SKILL.md + examples.md)

Test plan

• [] Original week1/day3.md / day3.part2.md / day4.md still match the videos (@clerk/nextjs@6.39.0 + / )
• [] file day3_v2.md landing page uses useAuth() (showSignedIn = isLoaded && isSignedIn)
• [] file day3.part2_v2.md / day4_v2.md do not mount the product until has?.({ plan: 'premium_subscription' })
• [] Skill in community_contributions/clerk-core3-auth/ converts SignedIn / SignedOut / Protect on "use client" pages via useAuth()