Nebula: Fix chat session randomly showing empty state after first prompt (#6744)

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## PR-Codex overview
This PR addresses an issue with updating the page URL in the `ChatPageContent.tsx` file due to changes in Next.js behavior. The existing method for updating the URL is commented out, and a temporary solution is proposed.

### Detailed summary
- Commented out the line: `window.history.replaceState({}, "", `/chat/${sessionId}`);`
- Added comments explaining that the URL update does not work anymore due to Next.js changes.
- Stated intention to not update the URL until a better solution is found.

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Author: MananTank

apps/dashboard/src/app/nebula-app/(app)/components/ChatPageContent.tsx

@@ -161,7 +161,9 @@ export function ChatPageContent(props: {
     (sessionId: string) => {
       _setSessionId(sessionId);
       // update page URL without reloading
-      window.history.replaceState({}, "", `/chat/${sessionId}`);
+      // THIS DOES NOT WORK ANYMORE!! - NEXT JS IS MONKEY PATCHING THIS TOO
+      // Until we find a better solution, we are just not gonna update the URL
+      // window.history.replaceState({}, "", `/chat/${sessionId}`);
 
       // if the current page is landing page, link to /chat
       // if current page is new /chat page, link to landing page