fix(llvm): Phase 131-10 - Smart console.log routing（Segfault修正）

## 問題
- Integer値をi8*ポインタに変換 → Segfault（Exit 139）

## 解決策
- String literal → nyash.console.log(i8*)
- Integer/Handle → nyash.console.log_handle(i64)

## 結果
- Case B (loop_min_while): LLVM outputs `0,1,2` ✅
- VM/LLVM完全パリティ達成

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/llvm_py/instructions/externcall.py

@@ -80,10 +80,30 @@ def lower_externcall(
         # Many call sites pass handles or pointers; we coerce below.
     }
 
+    # Phase 131-10: Smart console.log routing
+    # If console.log is called with a non-string-literal argument, use console.log_handle instead
+    actual_c_symbol = c_symbol_name
+    use_handle_variant = False
+
+    if llvm_name in ("nyash.console.log", "nyash.console.warn", "nyash.console.error"):
+        # Check if first argument is a string literal
+        if len(args) > 0:
+            first_arg = args[0]
+            is_string_literal = False
+            if resolver is not None and hasattr(resolver, 'string_ptrs'):
+                is_string_literal = first_arg in resolver.string_ptrs
+
+            # If NOT a string literal, use the _handle variant
+            if not is_string_literal:
+                use_handle_variant = True
+                # Extract method name (log, warn, error)
+                method = llvm_name.split('.')[-1]
+                actual_c_symbol = f"nyash.console.{method}_handle"
+
     # Find or declare function with appropriate prototype
     func = None
     for f in module.functions:
-        if f.name == c_symbol_name:
+        if f.name == actual_c_symbol:
             func = f
             break
     if not func:
@@ -91,6 +111,10 @@ def lower_externcall(
             ret_ty, arg_tys = sig_map[llvm_name]
             fnty = ir.FunctionType(ret_ty, arg_tys)
             func = ir.Function(module, fnty, name=c_symbol_name)
+        elif use_handle_variant:
+            # console.*_handle: (i64) -> i64
+            fnty = ir.FunctionType(i64, [i64])
+            func = ir.Function(module, fnty, name=actual_c_symbol)
         elif llvm_name.startswith("nyash.console."):
             # console.*: (i8*) -> i64
             fnty = ir.FunctionType(i64, [i8p])