feat(rbac)!: add Azure RBAC engine, FFI API, and cross-language tests (#577)

- add Azure RBAC condition interpreter and builtin evaluation in core (expressions, parser updates, evaluator, and test harness)
- introduce comprehensive RBAC YAML test suites and coverage for i
  - action/suboperation
  - strings
  - numbers
  - bools
  - IP
  - GUID
  - dates
  - times
  - lists
  - quantifiers (ForAnyOfAnyValues, ForAllOfAllValues)
- expose RBAC evaluation through FFI with an `rbac` feature flag enabled by default
- add C# `RbacEngine` wrapper + P/Invoke entrypoint and document usage in C# README
- expand C# tests to execute all RBAC YAML cases with per-case logging
- wire test assets into C# test output and centralize YAML dependency versions

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

bindings/ffi/src/lib.rs

@@ -14,6 +14,8 @@ mod engine;
 mod limits;
 mod lock;
 mod panic_guard;
+#[cfg(feature = "rbac")]
+mod rbac;
 #[cfg(feature = "rvm")]
 pub(crate) mod rvm;
 mod schema_registry;