feat: implement space hierarchy

- implement spaces hierarchy
- create expandable navigation drawer tiles
- display suggested rooms below joined rooms when in space
- everything works nested
- fix shared preferenced conflic with debug builds on Linux
- add [`package:async`](https://pub.dev/packages/async)

Signed-off-by: TheOneWithTheBraid <the-one@with-the-braid.cf>

pubspec.lock

@@ -72,7 +72,7 @@ packages:
     source: hosted
     version: "1.1.0"
   async:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: async
       url: "https://pub.dartlang.org"