Add Custom Sky generator for Sky Aesthetics (#667)

* Added Custom Sky generator

* Added 1.21.1 support

* fix config

* revert config change

* Fix assets config not working

* update url

* Fix merge conflict

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Co-authored-by: Misode <misoloo64@gmail.com>

src/app/services/Spyglass.ts

@@ -314,6 +314,7 @@ export class SpyglassService {
 							...Object.fromEntries(siteConfig.generators.filter(gen => gen.dependency).map(gen =>
 								[gen.path ?? gen.id, {
 									category: gen.id,
+									pack: gen.tags?.includes('assets') ? 'assets' : 'data',
 								}]
 							)),
 						},