closes #12664

This PR moves the client preloading logic into its own module and adds a new config option (name can be bikeshed) to completely disable configure link option preloading. It needs to be a config option because it's not a simple task to detect if there are no data-sveltekit-preload-* attributes in the app and automatically disable the listener for it.

TODO

• refactor to allow specifying which options can be used rather than disabling the whole setup

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