Update various types to use their own definitions

This commit refactors several modules to use the defined types from
`ast::types` and `ast::nodes` directly, rather than using fully
qualified paths. This improves code readability and reduces redundancy.

Specifically, the following changes were made:

- In `analyzer.rs`, `crate::ast::types::Identity` and
  `crate::ast::types::Purity` are now used directly.
- In `binder.rs`, `crate::ast::types::NodeIdentity`,
  `crate::ast::types::SourceLocation`,
  `crate::ast::types::RecordLayout`, and `crate::ast::types::Value` are
  now used directly.
- In `macros.rs`, types like `Address`, `VirtualId`, `NodeIdentity`,
  `SourceLocation`, `StaticType`, and `Purity` are now used directly.
- In `optimizer/engine.rs`, `Address<VirtualId>` is now used directly.
- In `type_checker.rs`, `BoundPhase`, `Signature`, `Keyword`, and
  `RecordLayout` are now used directly.
- In `environment.rs`, `CompilerScope`, `LocalInfo`, `CapturePass`,
  `AnalyzedPhase`, `NativeFunction`, and `Closure` are now used
  directly.
- In `nodes.rs`, `RecordLayout`, `Keyword`, `Purity`, and `StaticType`
  are now used directly.
- In `parser.rs`, `SourceLocation` and `NodeIdentity` are now used
  directly.
- In `rtl/math.rs`, `NativeFunction`, `Purity`, `Signature`,
  `StaticType`, `Value`, `RefCell`, and `Rc` are now used directly.
- In `rtl/streams.rs`, `ScalarValue`, `SeriesMember`, `Object`,
  `PipeFn`, `Value`, `VM`, `RingBuffer`, `RecordSeries`, `SeriesView`,
  `build_map_stream`, and `build_pipeline_node` are now used directly.
- In `rtl/type_registry.rs`, `RecordLayout`, `Keyword`, `Purity`,
  `Signature`, `StaticType`, and `Value` are now used directly.
- In `vm.rs`, `RecordSeries`, `SeriesView`, `build_map_stream`,
  `build_pipeline_node`, `StreamNode`, `Object`, and `PipeFn` are now
  used directly.
- In `utils/tester.rs`, `TypedNode` is now used directly.

src/ast/rtl/math.rs

@@ -1,6 +1,8 @@
 use crate::ast::environment::Environment;
-use crate::ast::types::{Purity, Signature, StaticType, Value};
+use crate::ast::types::{NativeFunction, Purity, Signature, StaticType, Value};
+use std::cell::RefCell;
 use std::f64::consts;
+use std::rc::Rc;
 
 pub fn register(env: &Environment) {
     // Constants
@@ -165,10 +167,10 @@ pub fn register(env: &Environment) {
                 fastrand::Rng::new()
             };
 
-            let prng = std::rc::Rc::new(std::cell::RefCell::new(rng));
+            let prng = Rc::new(RefCell::new(rng));
 
-            Value::Function(std::rc::Rc::new(crate::ast::types::NativeFunction {
-                func: std::rc::Rc::new(move |_args| Value::Float(prng.borrow_mut().f64())),
+            Value::Function(Rc::new(NativeFunction {
+                func: Rc::new(move |_args| Value::Float(prng.borrow_mut().f64())),
                 purity: Purity::Impure,
             }))
         },