Unable to add existing room to a space

### Steps to reproduce

1. I want to add an existing room to an existing space
2. In the space I tap the "New" --> "Add room", then I change to the "Existing" tab
3. I see a list of my rooms where I can select one or more rooms
4. And now? There is no kind of "Ready", "Save" or any other confirmation element. I'm stuck in the selection and can't perform the add.
Both text buttons "Cancel" and "Add" which are at the top of the windows of the "New" tab are simply not there in the "Existing" tab.


### Outcome

#### What did you expect?

I expect "Cancel" and "Add" action buttons to perform or cancel the operation.

#### What happened instead?

Nothing ... I can't do anything with the selected room.

### Your phone model

iPhone 14 Pro Max

### Operating system version

IOS 16.4.1

### Application version

Element 1.10.10.

### Homeserver

Synapse 1.81

### Will you send logs?

No

No source files or tests are named. Reproduce the flow in the iOS app by opening an existing space, choosing New → Add room → Existing, and selecting a room; the work is done when visible Cancel and Add actions let the user cancel or complete the operation.

Written by the indexing model from the issue text.