F consolidation

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include/caosdb/entity.h

@@ -558,6 +558,16 @@ private:
  * Container for Properties of Entities.
  *
  * Should only be instantiated and write-accessed by the owning entity.
+ *
+ * Note that iterating over the Property contents only works via references, since the Property copy
+ * constructor is deliberately disabled:
+ *
+ * \code
+ * // Accessing single properties as reference
+ * auto &property = my_properties.at(0);
+ * // Iterating via reference
+ * for (auto &property : my_properties) {...}
+ * \endcode
  */
 class Properties
   : public RepeatedPtrFieldWrapper<Property,