Support array properties in Duktape backend

It should be possible to create a `Property>("myArray", ...)` and access its elements from JS as `myObj.myArray[x]`.

Currently, I see two issues that must be addressed:
- [ ] the typed-library does not recognize `std::vector` as an array type, only `std::array`
- [ ] the Duktape backend does not expose arrays as such

Trace how the typed-library identifies std::array and how the Duktape backend exposes array properties, starting with Property>("myArray", ...). Done means std::vector is recognized as an array type and myObj.myArray[x] works from JavaScript.

Written by the indexing model from the issue text.