Refactor series implementation into its own module

This commit reorganizes the series-related code by moving the
`RingBuffer`, `ScalarSeries`, `ValueSeries`, `RecordSeries`,
`SeriesView`, and `SharedSeries` structs into a new
`src/ast/rtl/series/data.rs` file.

The `src/ast/rtl/series/mod.rs` file now contains the module
declaration, re-exports, and the `register` function for registering
series-related native functions with the environment. This improves code
organization and maintainability.

src/ast/environment.rs

@@ -19,7 +19,7 @@ use crate::ast::compiler::lambda_collector::LambdaCollector;
 use crate::ast::compiler::lowering::Lowering;
 use crate::ast::compiler::macros::{MacroEvaluator, MacroExpander, MacroRegistry};
 use crate::ast::compiler::optimizer::Optimizer;
-use crate::ast::compiler::specializer::{FunctionRegistry, MonoCache, Specializer};
+use crate::ast::compiler::specializer::{FunctionRegistry, MonoCache, RtlLookupFunc, Specializer};
 use crate::ast::rtl::{self, intrinsics};
 use crate::ast::types::{
     NativeFunction, NodeIdentity, Purity, SourceLocation, StaticType, Value,
@@ -28,8 +28,12 @@ use crate::ast::types::{
 use crate::ast::diagnostics::{DiagnosticLevel, Diagnostics};
 pub type PipelineGenerator = Box<dyn FnMut() -> bool>;
 
-const SYSTEM_LIB_SOURCE: &str = include_str!("system.myc");
-const SYSTEM_LIB_PATH: &str = "<embedded>/system.myc";
+const SYSTEM_LIB_SOURCE: &str = include_str!("rtl/prelude.myc");
+const SYSTEM_LIB_PATH: &str = "<embedded>/prelude.myc";
+
+fn make_rtl_lookup() -> RtlLookupFunc {
+    Rc::new(|name: &str, args: &[StaticType]| intrinsics::lookup(name, args))
+}
 
 pub struct CompilationResult {
     pub ast: Option<TypedNode>,
@@ -707,7 +711,7 @@ impl Environment {
             analyzed_registry: self.typed_function_registry.clone(),
         });
 
-        let rtl_lookup = Rc::new(|name: &str, args: &[StaticType]| intrinsics::lookup(name, args));
+        let rtl_lookup = make_rtl_lookup();
         let typed_reg = self.typed_function_registry.clone();
         let mono_cache = self.monomorph_cache.clone();
         let root_values = self.root_values.clone();
@@ -755,8 +759,7 @@ impl Environment {
                 let sub_registry = Rc::new(EnvFunctionRegistry {
                     analyzed_registry: typed_reg.clone(),
                 });
-                let sub_rtl_lookup =
-                    Rc::new(|name: &str, args: &[StaticType]| intrinsics::lookup(name, args));
+                let sub_rtl_lookup = make_rtl_lookup();
 
                 let sub_specializer = Specializer::new(
                     Some(sub_registry),

src/ast/rtl/series/mod.rs

@@ -0,0 +1,100 @@
+pub mod data;
+pub use data::*;
+
+use std::rc::Rc;
+
+use crate::ast::environment::Environment;
+use crate::ast::types::{Purity, RecordLayout, Signature, StaticType, Value};
+
+// ============================================================================
+// 5. Script Integration (RTL Registration)
+// ============================================================================
+
+pub fn register(env: &Environment) {
+    // (series lookback_limit template_or_type_keyword) -> Series
+    env.register_native_fn(
+        "series",
+        StaticType::Function(Box::new(Signature {
+            params: StaticType::Tuple(vec![StaticType::Int, StaticType::Any]),
+            ret: StaticType::Any,
+        })),
+        Purity::Impure,
+        |args: &[Value]| {
+            let lookback_limit = args[0].as_int().unwrap_or(0) as usize;
+            let arg = &args[1];
+            match arg {
+                Value::Keyword(k) => {
+                    match k.name().to_lowercase().as_str() {
+                        "float" => Value::Object(Rc::new(ScalarSeries::<f64>::new("FloatSeries", lookback_limit))),
+                        "int" | "datetime" => Value::Object(Rc::new(ScalarSeries::<i64>::new("IntSeries", lookback_limit))),
+                        "bool" => Value::Object(Rc::new(ScalarSeries::<bool>::new("BoolSeries", lookback_limit))),
+                        "text" => Value::Object(Rc::new(ValueSeries::new(lookback_limit))),
+                        _ => panic!("Unknown or unsupported series type keyword: :{}", k.name()),
+                    }
+                }
+                Value::Record(schema_layout, schema_values) => {
+                    // Interpret the record as a schema: { :field :type_keyword }
+                    let mut fields = Vec::with_capacity(schema_layout.fields.len());
+                    for (i, (name, _)) in schema_layout.fields.iter().enumerate() {
+                        let type_keyword = match &schema_values[i] {
+                            Value::Keyword(tk) => tk.name().to_lowercase(),
+                            _ => panic!("Field :{} in series schema must be a type keyword (e.g., :float, :int)", name.name()),
+                        };
+                        let ty = match type_keyword.as_str() {
+                            "float" => StaticType::Float,
+                            "int" => StaticType::Int,
+                            "bool" => StaticType::Bool,
+                            "datetime" => StaticType::DateTime,
+                            "text" => StaticType::Text,
+                            _ => panic!("Unsupported type keyword :{} for series field :{}", type_keyword, name.name()),
+                        };
+                        fields.push((*name, ty));
+                    }
+                    let final_layout = RecordLayout::get_or_create(fields);
+                    Value::Object(Rc::new(RecordSeries::new(final_layout, lookback_limit)))
+                }
+                _ => panic!("series expects a lookback_limit and a type keyword (:float, :int...) or a schema record (e.g., {{:price :float}})"),
+            }
+        },
+    );
+
+    // (push series value) -> Void
+    env.register_native_fn(
+        "push",
+        StaticType::Function(Box::new(Signature {
+            params: StaticType::Tuple(vec![StaticType::Any, StaticType::Any]),
+            ret: StaticType::Void,
+        })),
+        Purity::Impure,
+        |args: &[Value]| {
+            let (series_val, val) = (&args[0], &args[1]);
+
+            if let Value::Object(obj) = series_val {
+                if let Some(p) = obj.as_pushable_series() {
+                    p.push_value(val.clone());
+                    return Value::Void;
+                }
+                panic!("push expects a pushable series, got: {}", obj.type_name());
+            }
+            panic!("push expects a series object as the first argument")
+        },
+    );
+
+    // (len series) -> Int
+    env.register_native_fn(
+        "len",
+        StaticType::Function(Box::new(Signature {
+            params: StaticType::Tuple(vec![StaticType::Any]),
+            ret: StaticType::Int,
+        })),
+        Purity::Pure,
+        |args: &[Value]| {
+            if let Value::Object(obj) = &args[0]
+                && let Some(s) = obj.as_series()
+            {
+                return Value::Int(s.len() as i64);
+            }
+            Value::Int(0)
+        },
+    );
+}