feat: enhance login tracking and logout functionality

- Added session storage flag to track local login success, ensuring OAuth flows do not double track login events.
- Implemented tracking for logout events in both UserDropdown and AppSidebar components, resetting PostHog identity accordingly.
- Minor formatting adjustments in GoogleLoginButton and footer-new components for consistency.

surfsense_web/components/providers/PostHogProvider.tsx

@@ -3,6 +3,7 @@
 import { PostHogProvider as PHProvider } from "@posthog/react";
 import posthog from "posthog-js";
 import type { ReactNode } from "react";
+import { PostHogIdentify } from "./PostHogIdentify";
 
 interface PostHogProviderProps {
 	children: ReactNode;
@@ -11,5 +12,10 @@ interface PostHogProviderProps {
 export function PostHogProvider({ children }: PostHogProviderProps) {
 	// posthog-js is already initialized in instrumentation-client.ts
 	// We just need to wrap the app with the PostHogProvider for hook access
-	return <PHProvider client={posthog}>{children}</PHProvider>;
+	return (
+		<PHProvider client={posthog}>
+			<PostHogIdentify />
+			{children}
+		</PHProvider>
+	);
 }