moved callback to leptos root and improved design #880

Job	Run time
get-leptos-changed / Detect Source Change	9s
CI (integrations/utils) / Run ci (nightly)	2m 8s
CI (integrations/actix) / Run ci (nightly)	2m 3s
CI (integrations/viz) / Run ci (nightly)	2m 4s
CI (integrations/axum) / Run ci (nightly)	2m 2s
CI (leptos) / Run ci (nightly)	2m 5s
CI (leptos_config) / Run ci (nightly)	1m 45s
CI (leptos_dom) / Run ci (nightly)	2m 2s
CI (leptos_hot_reload) / Run ci (nightly)	1m 58s
CI (leptos_macro) / Run ci (nightly)	1m 50s
CI (leptos_reactive) / Run ci (nightly)	1m 57s
CI (leptos_server) / Run ci (nightly)	1m 50s
CI (meta) / Run ci (nightly)	2m 0s
CI (router) / Run ci (nightly)	1m 48s
CI (server_fn) / Run ci (nightly)	1m 50s
CI (server_fn_macro) / Run ci (nightly)	2m 3s
CI (server_fn/server_fn_macro_default) / Run ci (nightly)	2m 2s
	31m 36s

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