refactor: update better-auth configuration and clean up code

- Changed the version of "better-auth" to use a catalog reference in package.json and bun.lock for better dependency management.
- Removed unnecessary comments and cleaned up the code in various files to enhance readability and maintainability.
- Updated the authentication handling in hooks.server.ts to ensure proper token retrieval.
- Simplified the layout and structure of Svelte components for improved clarity and performance.

apps/web/src/routes/(dashboard)/+layout.server.ts

@@ -0,0 +1,9 @@
+import { api } from "@sgse-app/backend/convex/_generated/api";
+import { createConvexHttpClient } from "@mmailaender/convex-better-auth-svelte/sveltekit";
+
+export const load = async ({ locals }) => {
+  const client = createConvexHttpClient({ token: locals.token });
+
+  const currentUser = await client.query(api.auth.getCurrentUser, {});
+  return { currentUser };
+};