refactor(atoms): migrate to jotai-tanstack-query from custom reloadable atoms

Replace custom createReloadableAtom/createReloadableAtomFamily with
atomWithSuspenseQuery from jotai-tanstack-query, leveraging TanStack
Query's built-in caching, invalidation, and Suspense support.

- Add @tanstack/query-core and jotai-tanstack-query dependencies
- Create shared QueryClient instance (src/client/queryClient.ts)
- Migrate all data atoms (decks, cards, study, noteTypes) to atomWithSuspenseQuery
- Update page components to use .data destructuring and queryClient.invalidateQueries()
- Update all test files to use QueryClient for data hydration
- Remove src/client/atoms/utils.ts (no longer needed)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/src/client/queryClient.ts b/src/client/queryClient.ts
new file mode 100644
index 0000000..8743543
--- /dev/null
+++ b/src/client/queryClient.ts
@@ -0,0 +1,10 @@
+import { QueryClient } from "@tanstack/query-core";
+
+export const queryClient = new QueryClient({
+	defaultOptions: {
+		queries: {
+			staleTime: 0,
+			retry: false,
+		},
+	},
+});