migrate to swc 3.0.0 for next upgrade

[jantimon]

Update the SWC plugin and related dependencies for compatibility with Next.js 15

• ✅ All existing tests have been updated and pass
• ✅ Verified compatibility with Next.js 15 features

Version Updates

• 🔄 Upgraded Next.js from 14.2.4 to 15.0.2 (for our test pipeline and examples)
• ⚡ Updated @swc/core from 1.6.0 to 1.7.42 (only for our test pipeline)
• 🛠️ Updated swc_core from 0.279.0 to 3.0.2 and also the related SWC dev packages to their v3.0.x versions

Implementation Changes

• 🔨 Migrated from Fold to Pass API as per SWC's new visitor pattern
• 🔄 Replaced as_folder with visit_mut_pass
• 🔧 Updated function signatures to implement Pass trait
• 🚫 Temporarily removed cookie-based theming support due to Next.js 15's async cookies API

Breaking Changes Handled

• Switched to the new visitor pattern using Program.apply() and Fold
• Updated Ident to IdentName to match the new SWC APIs

Next 15 async

• The cookie usage in the example was temporary removed and will be addressed in a future update once we implement a solution compatible with Next.js 15's async cookies API

Closes #181

Special thanks to @kdy1 for:

• Pointing me to the migration guide in swc-project/swc#9680
• Immediately updating the SWC documentation to reflect the SWC breaking changes
• Offering guidance on implementing the new Pass API

[codspeed-hq]

CodSpeed Performance Report

Merging #196 will not alter performance

_{Comparing feature/migrate-to-swc-3 (b8df2df) with main (297b434)}

Summary

✅ 2 untouched benchmarks

[kdy1]

As a side note, I’m going to upgrade swc_core of next to v4 and it will be incompatible with v3 of swc_core.

There was important perf improvement, and it was a Wasm-breaking change

[jantimon]

good to know - we will upgrade once SWC 4 lands in next.js

[kdy1]

vercel/next.js#71683 is merged.
There were two breaking changes due to swc-project/swc#9717 (Revert PR) so the version is [email protected]

[jantimon]

thanks @kdy1 for all these insights - is this already part of nextjs 15.0.3-canary.8?

[changeset-bot]

🦋 Changeset detected

Latest commit: b8df2df

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
next-yak	Major
yak-swc	Major

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