refactor: integrate current user data across components

- Replaced instances of `authStore` with `currentUser` to streamline user authentication handling.
- Updated permission checks and user-related data retrieval to utilize the new `useQuery` for better performance and clarity.
- Cleaned up component structures and improved formatting for consistency and readability.
- Enhanced error handling and user feedback mechanisms in various components to improve user experience.

apps/web/src/lib/components/chat/PresenceManager.svelte

@@ -2,7 +2,6 @@
   import { useConvexClient } from "convex-svelte";
   import { api } from "@sgse-app/backend/convex/_generated/api";
   import { onMount } from "svelte";
-  import { authStore } from "$lib/stores/auth.svelte";
 
   const client = useConvexClient();