Query key factory and queryClient hygiene

Query keys are inline strings scattered across routes, hooks and components (["albums", options], ["albumReview", id], ["home"], ["artistID", id]...), and AdminDropdown reads the cache with a locally re-declared shape that's already drifted from the real one. Components also import queryClient directly from main.tsx, which creates an import cycle (main -> routes -> components -> main).

• Add a typed queryKeys factory module and replace every inline key
• Replace queryClient imports from @/main with the useQueryClient() hook
• Invalidations go through the factory so related keys stay consistent