Add method to get current server time in milliseconds in ModuleApi

changelog.d/18144.feature

@@ -0,0 +1 @@
+Introduced the get_current_time method in ModuleApi to provide the current server time in milliseconds, as wrapper around self.module_api._clock.time_msec() to avoid accessing private variables

synapse/module_api/__init__.py

@@ -1846,6 +1846,9 @@ async def set_displayname(
             deactivation=deactivation,
         )
 
+    def get_current_time(self) -> int:
+        """Returns the current server time in milliseconds."""
+        return self._clock.time_msec()
 
 class PublicRoomListManager:
     """Contains methods for adding to, removing from and querying whether a room