perf(vite): avoid duplicate JSON.stringify operation

[GalacticHypernova]

🔗 Linked issue

❓ Type of change

• 📖 Documentation (updates to the documentation, readme or JSdoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Save the stringified json to avoid a re-stringification.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

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[codspeed-hq]

CodSpeed Performance Report

Merging #24848 will improve performances by ×2.4

_{Comparing GalacticHypernova:patch-11 (e2a2919) with main (ba0d274)}

Summary

⚡ 3 improvements
✅ 5 untouched benchmarks

Benchmarks breakdown

	Benchmark	main	GalacticHypernova:patch-11	Change
⚡	minimal test fixture (types)	57 ms	42.5 ms	+34.13%
⚡	minimal test fixture	136 ms	57.5 ms	×2.4
⚡	basic test fixture (types)	607.3 ms	349 ms	+74.02%