fix(llvm): Phase 131-7 - Multi-pass vmap sync 修正（Branch bug 解消）

Phase 131-7: Multi-pass block lowering の vmap sync バグ修正

問題:
- Pass A (body instructions) が vmap_cur に値を保存
- Pass C (deferred terminators) が builder.vmap を参照
- → Pass A の値が Pass C に届かない
- → Branch condition が 0 に fallback → 無限ループ

修正:
- src/llvm_py/builders/block_lower.py (lines 237-248):
  - PHI-only フィルタを削除
  - 全ての値を global vmap に sync

変更ファイル:
- src/llvm_py/builders/block_lower.py: vmap sync 修正
- src/llvm_py/instructions/controlflow/branch.py: trace logging 追加
- src/llvm_py/instructions/unop.py: trace logging 追加
- src/llvm_py/llvm_builder.py: debug helpers 追加
- src/llvm_py/phi_wiring/wiring.py: trace logging 追加
- src/runner/modes/common_util/exec.rs: Python stdout 転送

結果:
- ✅ Branch bug 修正: ループが正しく終了
- ✅ 出力: 無限ループ → 3回で停止
- ❌ 新 bug 発見: ExternCall が null を受け取る（PHI 値の代わりに）

Next: Phase 131-8 (ExternCall argument handling 修正)

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

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

src/llvm_py/builders/block_lower.py

@@ -234,10 +234,12 @@ def lower_blocks(builder, func: ir.Function, block_by_id: Dict[int, Dict[str, An
             builder._deferred_terminators = {}
         if term_ops:
             builder._deferred_terminators[bid] = (bb, term_ops)
+        # Phase 131-7: Sync ALL created values to global vmap (not just PHIs)
+        # This ensures Pass C (deferred terminators) can access values from Pass A
         try:
             for vid in created_ids:
                 val = vmap_cur.get(vid)
-                if val is not None and hasattr(val, 'add_incoming'):
+                if val is not None:
                     try:
                         builder.vmap[vid] = val
                     except Exception: