Phase 12: VM/JIT identical execution tests + host API slot routing

ChatGPT5による統一実行パス実装：
- VM/JIT同一実行テスト追加（Array/Map/String/Instance）
- host_api slot経由呼び出し（NYASH_JIT_HOST_BRIDGE=1）
- extern_registry拡張（console系メソッドslot登録）
- CI: vm-jit-identical.yml（STRICT/非STRICT両系テスト）
- InstanceBox getField/setField slot 1,2統一

技術的改善：
- JIT: ops_ext委譲による統一メソッド解決
- VM: vtable/PIC/名前ベースフォールバック階層
- host_bridge: TLV encode/decode BoxRef対応
- C ABI: nyrt_host_api.h外部公開ヘッダー

テスト追加：
- identical_exec_collections: Array/Map操作一致
- identical_exec_instance: ユーザー定義Box一致
- identical_exec_string: StringBox操作一致
- host_reverse_slot: 逆引きslot解決テスト

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

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

src/tests/identical_exec_instance.rs

@@ -0,0 +1,85 @@
+#[cfg(test)]
+mod tests {
+    use std::sync::{Arc, RwLock};
+    use std::collections::HashMap;
+
+    use crate::backend::VM;
+    use crate::mir::{MirModule, MirFunction, FunctionSignature, BasicBlockId, MirInstruction, ConstValue, EffectMask, MirType};
+    use crate::box_trait::NyashBox;
+    use crate::interpreter::RuntimeError;
+
+    // Minimal Person factory: creates InstanceBox with fields [name, age]
+    struct PersonFactory;
+    impl crate::box_factory::BoxFactory for PersonFactory {
+        fn create_box(&self, name: &str, _args: &[Box<dyn NyashBox>]) -> Result<Box<dyn NyashBox>, RuntimeError> {
+            if name != "Person" { return Err(RuntimeError::InvalidOperation { message: format!("Unknown Box type: {}", name) }); }
+            let fields = vec!["name".to_string(), "age".to_string()];
+            let methods: HashMap<String, crate::ast::ASTNode> = HashMap::new();
+            let inst = crate::instance_v2::InstanceBox::from_declaration("Person".to_string(), fields, methods);
+            Ok(Box::new(inst))
+        }
+        fn box_types(&self) -> Vec<&str> { vec!["Person"] }
+        fn is_builtin_factory(&self) -> bool { true }
+    }
+
+    fn build_person_module() -> MirModule {
+        let mut module = MirModule::new("identical_person".to_string());
+        let sig = FunctionSignature { name: "main".into(), params: vec![], return_type: MirType::String, effects: EffectMask::PURE };
+        let mut f = MirFunction::new(sig, BasicBlockId::new(0));
+        let bb = f.entry_block;
+
+        let person = f.next_value_id();
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::NewBox { dst: person, box_type: "Person".into(), args: vec![] });
+
+        // person.setField("name", "Alice")
+        let k_name = f.next_value_id();
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::Const { dst: k_name, value: ConstValue::String("name".into()) });
+        let v_alice = f.next_value_id();
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::Const { dst: v_alice, value: ConstValue::String("Alice".into()) });
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::BoxCall { dst: None, box_val: person, method: "setField".into(), args: vec![k_name, v_alice], method_id: None, effects: EffectMask::PURE });
+
+        // person.setField("age", 25)
+        let k_age = f.next_value_id();
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::Const { dst: k_age, value: ConstValue::String("age".into()) });
+        let v_25 = f.next_value_id();
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::Const { dst: v_25, value: ConstValue::Integer(25) });
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::BoxCall { dst: None, box_val: person, method: "setField".into(), args: vec![k_age, v_25], method_id: None, effects: EffectMask::PURE });
+
+        // name = person.getField("name"); return name
+        let k_name2 = f.next_value_id();
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::Const { dst: k_name2, value: ConstValue::String("name".into()) });
+        let out_name = f.next_value_id();
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::BoxCall { dst: Some(out_name), box_val: person, method: "getField".into(), args: vec![k_name2], method_id: None, effects: EffectMask::PURE });
+        f.get_block_mut(bb).unwrap().add_instruction(MirInstruction::Return { value: Some(out_name) });
+
+        module.add_function(f);
+        module
+    }
+
+    #[cfg(feature = "cranelift-jit")]
+    #[test]
+    fn identical_vm_and_jit_person_get_set_slots() {
+        // Build runtime with Person factory
+        let mut rt_builder = crate::runtime::NyashRuntimeBuilder::new();
+        rt_builder = rt_builder.with_factory(Arc::new(PersonFactory));
+        let runtime = rt_builder.build();
+
+        // Build module
+        let module = build_person_module();
+
+        // VM (VTABLE on)
+        std::env::set_var("NYASH_ABI_VTABLE", "1");
+        let mut vm = VM::with_runtime(runtime);
+        let vm_out = vm.execute_module(&module).expect("VM exec");
+        let vm_s = vm_out.to_string_box().value;
+
+        // JIT（host-bridge on）
+        std::env::set_var("NYASH_JIT_HOST_BRIDGE", "1");
+        let jit_out = crate::backend::cranelift_compile_and_execute(&module, "identical_person").expect("JIT exec");
+        let jit_s = jit_out.to_string_box().value;
+
+        assert_eq!(vm_s, jit_s);
+        assert_eq!(vm_s, "Alice");
+    }
+}
+