docs: Reorganize release notes display

[sarina]

As per mocks from early 2024, arrange the release notes such that the differences between the Dev/Operator RNs and the Product or Feature-based RNs is clear for the current and upcoming releases.

Acceptance Criteria

The implementation should match the mock.

Mocks

Mock ("Teak" should be "Sumac"):

Implemented

Implemented (see sandbox):

[sarina]

@feoh could you click around the Redwood and Sumac pages and make sure they look alright to you?

[feoh]

Will do first thing in the morning! Let me know if you need it sooner.

[sarina]

Tomorrow's great, no hurry. Thanks for the heads up 😄

[sarina]

@feoh did you want a chance to review this before I merge it?

[feoh]

LGTM! Thanks!