chore: add typed ESLint checks #18

Refs WealthLedger/main#18. Keep Biome; add no Prettier dependencies.

src/features/tbank-connection/model/sync.test.tsx

@@ -56,7 +56,10 @@ describe("sync connection and session boundaries", () => {
 			const { wrapper, queryClient } = createQueryWrapper();
 			const published: string[] = [];
 			const unsubscribe = queryClient.getQueryCache().subscribe((event) => {
-				if (event.query.queryKey[1] === "/api/v1/tbank-sync/{id}") {
+				if (
+					(event.query.queryKey as readonly unknown[])[1] ===
+					"/api/v1/tbank-sync/{id}"
+				) {
 					const data = event.query.state.data as { now?: string } | undefined;
 					if (data?.now) published.push(data.now);
 				}
@@ -73,6 +76,7 @@ describe("sync connection and session boundaries", () => {
 			act(() => {
 				mutation = result.current.mutation.mutateAsync({ body: screen });
 			});
+			// eslint-disable-next-line vitest/valid-expect -- Attach rejection handling before releasing the request; the assertion is awaited below.
 			const discarded = expect(mutation).rejects.toMatchObject({
 				name: "AbortError",
 			});