Rework async interface internal metaclasses

Instead of multiple different _private attributes use only two:

* `_dbus`: contains either remote objects metadata such as service
  name, object path and attached bus or local object metadata.
* `_dbus_meta`: contains interface class metadata such as D-Bus
  member names to python attributes and the reverse.

All descriptor protocols now return different classes based on
if the D-Bus element was accessed from a proxy or local object.
However, the API should remain the same.

src/sdbus/autodoc.py

@@ -23,12 +23,12 @@
 
 from sphinx.ext.autodoc import AttributeDocumenter, MethodDocumenter
 
-from .dbus_proxy_async_method import DbusMethodAsyncBinded
+from .dbus_proxy_async_method import DbusMethodAsyncClassBind
 from .dbus_proxy_async_property import (
     DbusPropertyAsync,
-    DbusPropertyAsyncBinded,
+    DbusPropertyAsyncClassBind,
 )
-from .dbus_proxy_async_signal import DbusSignalAsync, DbusSignalBinded
+from .dbus_proxy_async_signal import DbusSignalAsync, DbusSignalAsyncClassBind
 
 if TYPE_CHECKING:
     from typing import Any, Dict
@@ -38,13 +38,13 @@
 
 class DbusMethodDocumenter(MethodDocumenter):
 
-    objtype = 'DbusMethodAsyncBinded'
+    objtype = 'DbusMethodAsyncClassBind'
     directivetype = 'method'
     priority = 100 + MethodDocumenter.priority
 
     @classmethod
     def can_document_member(cls, member: Any, *args: Any) -> bool:
-        return isinstance(member, DbusMethodAsyncBinded)
+        return isinstance(member, DbusMethodAsyncClassBind)
 
     def import_object(self, raiseerror: bool = False) -> bool:
         self.objpath.append('dbus_method')
@@ -68,13 +68,13 @@ def add_content(self,
 
 class DbusPropertyDocumenter(AttributeDocumenter):
 
-    objtype = 'DbusPropertyAsyncBinded'
+    objtype = 'DbusPropertyAsyncClassBind'
     directivetype = 'attribute'
     priority = 100 + AttributeDocumenter.priority
 
     @classmethod
     def can_document_member(cls, member: Any, *args: Any) -> bool:
-        return isinstance(member, DbusPropertyAsyncBinded)
+        return isinstance(member, DbusPropertyAsyncClassBind)
 
     def import_object(self, raiseerror: bool = False) -> bool:
 
@@ -109,13 +109,13 @@ def add_content(self,
 
 class DbusSignalDocumenter(AttributeDocumenter):
 
-    objtype = 'DbusSignalBinded'
+    objtype = 'DbusSignalAsyncClassBind'
     directivetype = 'attribute'
     priority = 100 + AttributeDocumenter.priority
 
     @classmethod
     def can_document_member(cls, member: Any, *args: Any) -> bool:
-        return isinstance(member, DbusSignalBinded)
+        return isinstance(member, DbusSignalAsyncClassBind)
 
     def import_object(self, raiseerror: bool = False) -> bool:
 

src/sdbus/dbus_common_elements.py

@@ -30,6 +30,7 @@
 from .sd_bus_internals import is_interface_name_valid, is_member_name_valid
 
 if TYPE_CHECKING:
+    from asyncio import Queue
     from types import FunctionType
     from typing import (
         Any,
@@ -45,7 +46,7 @@
 
     T = TypeVar('T')
 
-    from .sd_bus_internals import SdBus
+    from .sd_bus_internals import SdBus, SdBusInterface
 
 
 class DbusSomethingCommon:
@@ -318,6 +319,15 @@ def __init__(
         )
 
 
+class DbusLocalObjectMeta:
+    def __init__(self) -> None:
+        self.activated_interfaces: List[SdBusInterface] = []
+        self.serving_object_path: Optional[str] = None
+        self.attached_bus: Optional[SdBus] = None
+        self.local_signal_queues: Dict[
+            Tuple[str, str], Set[Queue[Any]]] = {}
+
+
 class DbusClassMeta:
     def __init__(self) -> None:
         self.dbus_member_to_python_attr: Dict[str, str] = {}