[POC] Use direct dependency on react-query/core, make all results reactive

[benbender]

This is a proof of concept porting svelte-query over to directly use react-query/core as it's foundation and only be a thin layer on top to adapt it to svelte[kit].

• [x] All dependencies updated
• [x] Outdated sapper examples removed
• [x] Port to directly utilize react-query/core
• [x] Removed Svelte-components and return reactive stores from useQuery(), useMutation, etc...
• [x] Adapt APIs & exports from vue-query & react-query/react
• [x] Make stories work and tests green
• [x] Basic, rough example with sveltekit
• [x] Tests green (needed to adapt a few), Storybook-stories generally working
• [ ] Add devtools
• [ ] Testing
• [ ] Finalization
• [ ] Adaption to be "sveltier" and hook into sveltekit-Apis like load() or the hooks-mechanism (half done)

The port generally went really smooth and I think that is the direction to go with this package. That said, be warned, it's a rough POC with near to no testing and some rough edges to be worked out. Play with it. Have fun. But don't bet your childrens lives on it!

Would love to hear some feedback/thoughts/critics/whatever :)

[benbender]

As I don't have any sparetime for this project atm, I'm closing this for now.