fix: Thumbnail image too big

[LautaroPetaccio]

This PR does the following:

• Fixes a default value that resulted in all thumbnails to be 1024px in size.
• Makes the assets be 256px in size.
• Makes the wearable thumbnails to be 512px in size.
• Fetches the thumbnail to generate the catalyst image without cache.

[vercel]

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[coveralls]

Pull Request Test Coverage Report for Build 1259259017

• 1 of 4 (25.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.01%) to 5.408%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/lib/getScreenshot.ts	0	1	0.0%
src/modules/item/utils.ts	1	3	33.33%

Totals
Change from base Build 1258869761:	0.01%
Covered Lines:	579
Relevant Lines:	8941

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💛 - Coveralls