Quick start button disappears from the top bar mid-flow - you have to go back to where it respawns to continue

Bug Description

Please describe.

Working through the Quick start checklist as a first-time user. Completing or skipping a step populates fine — the checklist tracks progress correctly. The problem is the Quick start button doesn't persist in the top bar: click into a task, end up on another page, and the button is gone. To carry on with the checklist you have to navigate back to a page where it respawns.

If you save on the page you're configuring and the checklist doesn't resurface, and you're mid-flow, it breaks that flow. The checklist works as a tracker but not as a guide — the thread you're meant to be following keeps physically disappearing, and a new user mid-setup is exactly the person with the least spare attention for re-finding it. Seventeen steps is seventeen chances to lose the thread.

Suggested fix: keep the Quick start button pinned in the top bar on every screen while the checklist is incomplete — or resurface the panel when a step's task is saved so the flow carries you to the next one.

Screenshot attached.

How to reproduce

1. As a new user, open the Quick start checklist from the top bar and click into any step (e.g. "Create your first insight")
2. Complete or save the task on the page it takes you to
3. Note the Quick start button is no longer in the top bar — navigate back toward the home/insights screen to find where it reappears

Debug info

- [X] PostHog Cloud, Debug information: Session: https://us.posthog.com/project/sTMFPsFhdP1Ssg/replay/019f4fc6-a528-71f7-b12f-4382700a7bd0?t=0
Admin (internal): http://go/adminOrgEU/019f3d5d-3e60-0000-a7f3-58579a754bba (project ID 218385)
- [ ] PostHog Hobby self-hosted with `docker compose`, version/commit: [please provide]
- [ ] PostHog self-hosted with Kubernetes (deprecated, see [`Sunsetting Kubernetes support`](https://posthog.com/blog/sunsetting-helm-support-posthog)), version/commit: [please provide]

Start by reproducing the Quick start checklist flow from the top bar, following the example step such as “Create your first insight,” then inspect the top-bar and checklist entry points involved when navigating to and saving the task. Done means the Quick start button remains available on every screen while the checklist is incomplete, or the panel resurfaces after saving so the user can continue to the next step.