App Layout: last UI tweaks before RC

[gileluard]

We need to tweak some of the copy / images before release the new App Layout experience:

• change the copy of the empty section (no result found) for:
  Nothing found.
  Try adjusting your search.
• Empty invites
• Empty space
• Unread tab
• No spaces
• All chats

[amshakal]

Empty invites: https://www.figma.com/file/Hw4gjP3pknMZUir8jQqmWH/%5BMobile%5D-IA-early-proposals?node-id=4082%3A172522

[niquewoodhouse]

@gileluard there were some empty states for unread and space:

I've added here:

• Empty space
• Unread tab
• No spaces
• All chats

@daniellekirkwood I changed a few of these from the previous proposal, lmk if you want to discuss

[niquewoodhouse]

@gileluard all feedback has been given and made on the space release experience, the changes were

• New copy on all steps
• New images on all steps
• Remove first step

And there was a suggestion from n4d to change the button behaviour. If you think there's time to do it, lets do it but otherwise please avoid this change.