* feat: audit policy collection aliases
provides a means to alias collections in @@allow collections by extending the ast
this allows for utilizing collections inside of @@allow like:
```
memberships?[m,
auth().memberships?[
tenantId == m.tenantId ...
]
]
```
* fix: code review comments + syntax fixes
* refactor: extract collection predicate binding to its own language construct (#2)
- adjusted language processing chain accordingly
- fixed several issues in policy transformer/evaluator
- more test cases
* addressing PR comments
---------
Co-authored-by: Yiming Cao <yiming@whimslab.io>
Co-authored-by: ymc9 <104139426+ymc9@users.noreply.github.com>