Clean and simplify Nuxt utility

[cnotv]

Summary

Fixes #11196

• Removed a lot of unused code and unnecessary exports
• Moved within files single use cases
• Merged remaining functions with init helper
• Added comments
• Updated code to avoid reassignments or confusion, it should help with the migration

Occurred changes and/or fixed issues

Technical notes summary

Areas or cases that should be tested

Areas which could experience regressions

Screenshot/Video

Checklist

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