🧹 refactor: box_methods.rs大掃除完全成功 - 8モジュールに機能分離

🏗️ アーキテクチャ大幅改善:
• 1822行巨大ファイル → 8つの論理的モジュールに完全分割
• 機能別責任分離でメンテナンス性向上
• ゼロ破壊的変更 - 既存機能すべて正常動作

📂 新モジュール構造:
• basic_methods.rs - StringBox/IntegerBox/BoolBox/FloatBox
• collection_methods.rs - ArrayBox/MapBox
• io_methods.rs - FileBox/ResultBox
• system_methods.rs - TimeBox/DateTimeBox/TimerBox/DebugBox
• math_methods.rs - MathBox/RandomBox
• async_methods.rs - FutureBox/ChannelBox
• web_methods.rs - WebDisplayBox/WebConsoleBox/WebCanvasBox(WASM)
• special_methods.rs - MethodBox/SoundBox

✨ コード品質向上:
• 可読性 - 機能別分離で理解容易
• 保守性 - 変更影響の局所化
• 拡張性 - 新機能追加が簡単
• テスト性 - 単体テスト作成容易

🎯 プロフェッショナルレベルのコードベース完成\!
Everything is Box哲学の美しい実装構造達成

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

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

src/interpreter/mod.rs

@@ -9,7 +9,7 @@
 use crate::ast::{ASTNode, BinaryOperator, CatchClause};
 use crate::box_trait::{NyashBox, StringBox, IntegerBox, BoolBox, VoidBox, AddBox, SubtractBox, MultiplyBox, DivideBox, CompareBox, ArrayBox, FileBox, ResultBox, ErrorBox, FutureBox};
 use crate::instance::InstanceBox;
-use crate::channel_box::{ChannelBox, MessageBox};
+use crate::channel_box::ChannelBox;
 use crate::boxes::math_box::{MathBox, FloatBox, RangeBox};
 use crate::boxes::time_box::{TimeBox, DateTimeBox, TimerBox};
 use crate::boxes::map_box::MapBox;
@@ -17,11 +17,16 @@ use crate::boxes::random_box::RandomBox;
 use crate::boxes::sound_box::SoundBox;
 use crate::boxes::debug_box::DebugBox;
 use crate::method_box::MethodBox;
+
+// 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;
 
 // Module declarations  
+mod async_methods;
 mod box_methods;
 mod core;
 mod expressions;
@@ -29,6 +34,11 @@ mod statements;
 mod functions;
 mod objects;
 mod io;
+mod methods;
+mod math_methods;
+mod system_methods;
+mod web_methods;
+mod special_methods;
 
 // Main interpreter implementation - will be moved from interpreter.rs