Memory faults with user-defined callables usage

[flexferrum]

• 1. Use after free with callables as a reflected property

{{ foo.setBar(4) }} will cause a use after free when attempting to invoke the callable property setBar.

• 2. Dangling reference with user-defined callables returning a reflected object

{% set foo = callable() %} {{ foo.bar }} there is a dangling reference in the property accessor for foo.

[flexferrum]

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