[FEATURE] Keyword 'here' work for normal abilities in nodes and walkers

[Jayanaka-98]

Describe the idea

Currently in data-spatial programming in jaclang, when referred to as 'here' within an ability of a walker which has a with <node> entry; statement, it will refer the current node which the walker is currently on. But when doing the same within a normal ability without the with <> entry statement, an error will be produced. It feels trivial that,

• All abilities defined within a walker should have access to the here node, regardless of the with <> entry statement.
• All abilities defined within a node should have access to the here walker, regardless of the with <> entry statement.