fix sharing app instances, clarify contract

src/ansys/mechanical/core/embedding/app.py

@@ -121,13 +121,13 @@
 
         if BUILDING_GALLERY:
             if len(INSTANCES) != 0:
                 instance: App = INSTANCES[0]
                 instance._share(self)
                 if db_file != None:
                     self.open(db_file)
                 return
         if len(INSTANCES) > 0:
             raise Exception("Cannot have more than one embedded mechanical instance!")
         version = kwargs.get("version")
         self._version = initializer.initialize(version)
         configuration = kwargs.get("config", _get_default_addin_configuration())
@@ -297,27 +297,27 @@
         they all point to the same underlying application
         object. Because of that, special care needs to be
         taken to properly share the state. Other will be
-        a "weak reference", which doesn't own anything."""
-
+        a "weak reference", which doesn't own anything.
+        """
         # the other app is not expecting to have a project
         # already loaded
         self.new()
 
         # set up the type hint (typing.Self is python3.11+)
         other: App = other
 
         # copy `self` state to other.
         other._app = self._app
         other._version = self._version
         other._poster = self._poster
         other._updated_scopes = self._updated_scopes
 
         # all events will be handled by the original App instance
         other._subscribed = False
 
         # finally, set the other disposed flag to be true
         # so that the shutdown sequence isn't duplicated
         other._disposed = True
 
     def _subscribe(self):
         try: