Performance improvement when viewing MemoryManager in debugger

Author: mrexodia

src/dumpulator/memory.py

@@ -412,3 +412,6 @@ def set_region_info(self, addr: int, info: Any, *, size=0):
                 return False
             region.info = info
         return True
+
+    def __repr__(self):
+        return f"MemoryManager(regions={len(self._regions)}, committed={len(self._committed)})"