Remove direct insert in Navigation block in favour of improving the Link UI search

[getdave]

Let's avoid surfacing the variations of the Link block, instead focusing on the concept of adding an item to the navigation. This would reduce the need to decide what type of block to add, before searching for the item to be added.

This requires the following:

• When clicking the inserter in the Navigation block, no block should be auto inserted. Instead, display the Link UI.
• Consider a filter mechanic within the Link UI, which defaults to Posts and Pages. This will service 80% of the use cases whilst also improving the likelihood of searching returning useful results. An alternative would be to allow all results by default, like the Custom Link. Having a method to filter the results increases the likelihood of finding relevant content (specifically pages).

Visual (Link inserter)

CleanShot.2023-04-28.at.16.02.01.mp4

Visual (Filtering)

In this visual I am opting to search for a post category:

CleanShot.2023-04-28.at.15.44.28.mp4

Co-authored by @richtabor.

[richtabor]

This proposal here could work in tandem with the suggestions here.