refactor: Gemini/ChatGPT collaborative refactoring + build fixes

Major changes:
- Split runner module: 1358→580 lines (via Gemini)
- Create new modules: dispatch.rs, selfhost.rs, pipeline.rs, pipe_io.rs
- Fix build errors from incomplete method migrations
- Add warning to CLAUDE.md about JIT/Cranelift not working
- Create interpreter.rs mode module
- Refactor loop builder into separate module

Build status:
- ✅ Executable builds successfully
- ✅ Basic execution works (tested with print)
- ⚠️ 106 warnings remain (to be cleaned up next)
- ⚠️ execute_mir_mode still in mod.rs (needs further migration)

Note: ChatGPT correctly fixed runner.execute_mir_mode() calls
that I incorrectly changed to super::modes::mir::

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/interpreter/core.rs

@@ -31,6 +31,7 @@ pub(crate) fn debug_log(msg: &str) {
 }
 
 // Conditional debug macro - unified with utils::debug_on()
+#[allow(unused_macros)]
 macro_rules! debug_trace {
     ($($arg:tt)*) => {
         if crate::interpreter::utils::debug_on() { eprintln!($($arg)*); }

src/interpreter/eval.rs

@@ -1,7 +1,7 @@
 //! Evaluation entry points: execute program and nodes
 
 use crate::ast::ASTNode;
-use crate::box_trait::{NyashBox, VoidBox, StringBox};
+use crate::box_trait::{NyashBox, VoidBox};
 use super::{NyashInterpreter, RuntimeError, ControlFlow};
 
 impl NyashInterpreter {

src/interpreter/expressions/mod.rs

@@ -22,7 +22,7 @@ use std::sync::Arc;
 impl NyashInterpreter {
     /// Build closure environment by capturing 'me' and free variables by value (P1)
     fn build_closure_env(&mut self, params: &Vec<String>, body: &Vec<ASTNode>) -> Result<crate::boxes::function_box::ClosureEnv, RuntimeError> {
-        use std::collections::{HashSet, VecDeque};
+        use std::collections::HashSet;
         let mut env = crate::boxes::function_box::ClosureEnv::new();
         // Capture 'me' if bound
         if let Ok(mev) = self.resolve_variable("me") { env.me_value = Some(Arc::downgrade(&mev)); }

src/interpreter/methods/p2p_methods.rs

@@ -8,7 +8,6 @@ use crate::interpreter::RuntimeError;
 use crate::ast::ASTNode;
 use crate::box_trait::{NyashBox, StringBox};
 use crate::boxes::{IntentBox, P2PBox};
-use crate::box_trait::BoolBox;
 
 impl NyashInterpreter {
     /// IntentBoxのメソッド実行 (RwLock版)

src/interpreter/methods/system_methods.rs

@@ -7,7 +7,7 @@
  */
 
 use crate::ast::ASTNode;
-use crate::box_trait::{NyashBox, VoidBox, StringBox, BoolBox};
+use crate::box_trait::{NyashBox, BoolBox};
 use crate::boxes::gc_config_box::GcConfigBox;
 use crate::boxes::debug_config_box::DebugConfigBox;
 use crate::interpreter::{NyashInterpreter, RuntimeError};
@@ -168,4 +168,4 @@ impl NyashInterpreter {
             }),
         }
     }
-}
+}

src/interpreter/mod.rs

@@ -19,7 +19,6 @@ use crate::boxes::debug_box::DebugBox;
 // WASM-specific Box types (conditionally included)
 #[cfg(target_arch = "wasm32")]
 use crate::boxes::web::{WebDisplayBox, WebConsoleBox, WebCanvasBox};
-use crate::finalization;
 use crate::exception_box;
 use std::collections::HashMap;