feat: persistent cache in production mode wait for save to complete

[jerrykingxyz]

Summary

1. Persistent cache waits for storage saves to complete in production mode and exposes errors to compile diagnostics.
2. Persistent cache in development mode does not wait for save to complete, only prints storage errors when it ends.

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[netlify]

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[codspeed-hq]

CodSpeed Performance Report

Merging #8777 will not alter performance

_{Comparing jerrykingxyz:cache (edcf14d) with main (22f3bb0)}

Summary

✅ 1 untouched benchmarks