fix: ensure new assets cache at build start, fix #3271

[patak-dev]

Description

See #3271 and previous work by @CHOYSEN #3480

Moved the cache definitions before the plugin as they are now referenced by the hooks (following the style of the caches for the CSS plugin)

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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