MNT: Add getters for some protected Entity parameters

src/linkahead/common/models.py

@@ -200,6 +200,15 @@ class Entity:
 
         return self._wrapped_entity.version
 
+    @property   # getter for _cuid
+    def cuid(self):
+        # Set if None?
+        return self._cuid
+
+    @property   # getter for _flags
+    def flags(self):
+        return self._flags.copy()   # for dict[str, str] shallow copy is enough
+
     @version.setter
     def version(self, version: Optional[Version]):
         self._version = version