Space Nesting

[jackedproxy]

Describe the problem

Our Community Space has nested Categorical Spaces, along with a couple of those category Spaces having a third layer of Spaces for more specific things.

Use-case
--Homeserver Root Space
---- Gaming <- Works Nested
-------- Game#1 <- Does not work nested under Gaming, and appears under Homeserver Root Space instead.
------------ Room#1
------------ Room#2
--------- Game#2 <- Does not work nested under Gaming, and appears under Homeserver Root Space instead.
------------ Room#1
------------ Room#2

Describe the solution you'd like

Would be great to have these nested correctly, which is the case in other clients such as Commet or Element.

Game#1 Space should be able to nest under Gaming Space

Alternatives considered

The Spaces are still accessible, but would be nice to have nest displayed correctly.

Additional context

N/A - Happy to answer questions for any extra details needed.

[KaceCottam]

Hi! I was thinking of taking a crack at this.
I was wondering what kind of features we would want from this?

I am going to bring over 7w1's comment from the last repo:

linking this here to look into later/for anyone who chooses to tackle this: cinnyapp/cinny#2385
that pr only has rendering so we'd want to add another add space button to every space and somehow implement dragging for spaces themselves ideally

So far I am getting the following:

• Rendering: Render subspaces under the parent space using indentation or some other marker
• Rendering: Collapsing parent space will also hide all subspaces
• Rendering: Display is working in both the lobby and sidebar
• UI Interaction: "Add Space" button to every space
• UI Interaction: Ability to drag spaces

Since the UI Interactions aren't quite clear to me, I was going to start with the rendering side of things.