🏗️ feat: Phase 9.78b準備 - インタープリター・VM統合アーキテクチャ設計

Phase 9.78b: Codexの天才的分析に基づくアーキテクチャ再設計準備

## 📋 実施内容
1. Codex分析結果のアーカイブ
   - 実装詳細共有 → モデル共有・実行時共有への転換提案
   - 8ステップの段階的実装計画

2. Phase 9.78a作業の保存
   - MIR生成でのNewBox命令統一（保持）
   - ScopeTracker基本実装（一時コメントアウト）
   - VM拡張の方向性（TODOコメント付き）

3. ビルドエラー修正
   - ScopeTrackerインポート問題を一時的に解決
   - ビルド成功（警告のみ）

## 📚 作成ドキュメント
- architecture-redesign-proposal.md - Codexの設計提案
- phase_9_78b_interpreter_architecture_refactoring.md - 実装計画
- codex-analysis/* - 分析結果アーカイブ

## 🎯 次のステップ
Phase 9.78b Step 1: BoxDeclarationをcore::modelへ移動

src/scope_tracker.rs

@@ -0,0 +1,73 @@
+/*!
+ * ScopeTracker - Track Box instances for proper lifecycle management
+ * 
+ * Phase 9.78a: Unified Box lifecycle management for VM
+ */
+
+use std::sync::Arc;
+use crate::box_trait::NyashBox;
+
+/// Tracks Box instances created in different scopes for proper fini calls
+pub struct ScopeTracker {
+    /// Stack of scopes, each containing Boxes created in that scope
+    scopes: Vec<Vec<Arc<dyn NyashBox>>>,
+}
+
+impl ScopeTracker {
+    /// Create a new scope tracker
+    pub fn new() -> Self {
+        Self {
+            scopes: vec![Vec::new()], // Start with one root scope
+        }
+    }
+    
+    /// Enter a new scope
+    pub fn push_scope(&mut self) {
+        self.scopes.push(Vec::new());
+    }
+    
+    /// Exit current scope and call fini on all Boxes created in it
+    pub fn pop_scope(&mut self) {
+        if let Some(scope) = self.scopes.pop() {
+            // Call fini in reverse order of creation
+            for arc_box in scope.into_iter().rev() {
+                // For now, fini handling is simplified
+                // In a full implementation, we would check if the Box has a fini method
+                // and call it appropriately
+                // TODO: Implement proper fini dispatch
+                let _ = arc_box; // Suppress unused warning
+            }
+        }
+        
+        // Ensure we always have at least one scope
+        if self.scopes.is_empty() {
+            self.scopes.push(Vec::new());
+        }
+    }
+    
+    /// Register a Box in the current scope
+    pub fn register_box(&mut self, nyash_box: Arc<dyn NyashBox>) {
+        if let Some(current_scope) = self.scopes.last_mut() {
+            current_scope.push(nyash_box);
+        }
+    }
+    
+    /// Clear all scopes (used when resetting VM state)
+    pub fn clear(&mut self) {
+        // Pop all scopes and call fini
+        while self.scopes.len() > 1 {
+            self.pop_scope();
+        }
+        
+        // Clear the root scope
+        if let Some(root_scope) = self.scopes.first_mut() {
+            root_scope.clear();
+        }
+    }
+}
+
+impl Default for ScopeTracker {
+    fn default() -> Self {
+        Self::new()
+    }
+}