feat: Add UI elements to modify navigation display

[enjeck]

Part of #1177 and #1193

Todo

• ensure it works when you update a context
• ensure it works for owners and recipients too
• Discuss the UI and copy
• Ensure self-shares to the owner are deleted when share is deleted

[enjeck]

@nextcloud/designers Do you have any thoughts on how to go about the following?

We are trying to have settings where users can decide whether or not a Tables Application shows up in their navbar:

For the owners of the application, there are three possible default options to choose from. I feel like this could be reworded or made more succinct. See the "Navigation bar display" section in the image:

For share recipients, there's a checkbox. Not sure the wording or design is good enough:

[jancborchardt]

@enjeck nice!

So unless I misunderstand something, the settings seem can be simplified. As admins are also just users, they can use the navigation preference like everyone else.

The main settings should only say:

[ ] Show in app list

As a single checkbox, no subheading needed. It can have a color-text-maxcontrast sentence below saying "This can be overridden by a per-account preference."

For the left navigation entry, same wording and setting

[ ] Show in app list

[enjeck]

So unless I misunderstand something, the settings seem can be simplified. As admins are also just users, they can use the navigation preference like everyone else.

@jancborchardt This is not possible now, from what I see. There's no option for an owner to modify just their visibility, without affecting share recipients. And I'm not sure why it's not supported. I'll clarify at #1193 and see what can be changed

[enjeck]

So here are the challenges we've faced so far: Since navigation display setting is tied to shares, there is an additional share from the owner of an application to themselves. From discussions with @blizzz, we believe this is not good practice, but it's what it takes to get a better UX at the moment. The problem we have encountered now is that for owners of an application, the modifying the display does not work properly like with the sharees. So the plan now is:

• when disabling, set values that are "shown to all" to "show to all, but me"
• when enabled, set values that are "show to all, but me" to "show to all"