Re-order series in graphs

[kjetilk-kontali]

Feature request

Is your feature request related to a problem?

When adding series to an existing chart it's driving my OCD insane when I can't re-order the series.

Describe the solution you'd like

Being able to drag/move a given series up/down in the list of series for a graph. E.g., in this graph I would like to have "Industry" as the 6th item:

And a real bonus if I can be able to choose the coloring of series as well :)

Describe alternatives you've considered

Manually change the existing series, but adding a new series at the top would then mean that I need to change ALL series in the chart...

Additional context

Debug info

- [x] PostHog Cloud, Debug information: 
Session: https://us.posthog.com/project/sTMFPsFhdP1Ssg/replay/01944add-191b-79fb-8a29-01444f7fe2f0?t=358
Admin: http://go/adminOrgUS/018a16ba-0884-0000-5dac-74b1a2a08ff6 (project ID 34082)
Sentry: http://go/sentryUS/34082
- [ ] 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]