Joining another server no longer opens an empty player

connect() kept the last server's state while dialling the next; the
shell saw its media on arrival and opened the player (full, on a
friend's server) over the new, empty one.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/desktop/pubspec.lock

@@ -865,14 +865,14 @@ packages:
       path: "../../packages/core"
       relative: true
     source: path
-    version: "1.2.0"
+    version: "1.3.0"
   sync_relay_server:
     dependency: "direct main"
     description:
       path: "../../packages/server"
       relative: true
     source: path
-    version: "1.2.0"
+    version: "1.3.0"
   synchronized:
     dependency: transitive
     description: