Replace Jotai atoms with local state, add Suspense for PPR compatibility

- Delete filterable-row, backup-schedule, integrations, and system-health
  atom files; replace with useState/useTransition + server action calls
- Replace /api/explore/discover route with discoverByGenre server action;
  refactor FilterableTitleRow to call it directly via useTransition
- Wrap PagesLayout and AuthLayout children in Suspense to fix dynamic
  rendering errors during PPR static generation; remove StoreProvider
- Sequence ExplorePage session fetch before TMDB calls to prevent
  build-time requests during static generation
- Drop unnecessary "use client" directives from dashboard and person
  components that have no client-side hooks or browser API usage
- Improve Dockerfile: add bun install layer cache mount, copy
  .next/cache from builder, reorder ENV declarations

lib/atoms/update-check.ts

@@ -1,7 +1,7 @@
 import { atomWithStorage, createJSONStorage } from "jotai/utils";
 
-export const updateToastShownAtom = atomWithStorage<boolean>(
-  "sofa:update-toast-shown",
-  false,
+export const updateToastDismissedVersionAtom = atomWithStorage<string | null>(
+  "sofa:update-toast-dismissed-version",
+  null,
   createJSONStorage(() => sessionStorage),
 );