fix(tpv): 帧池访问改 Value 视图 + ConstNull 补 name 参数

- GlobalVariable 非 Value 子类，create/destroy 直接 build_load/store
  按 Value 布局读字段错位（Ty 读到 void、Name 为空）→ 生成
  "load i64, void" 非法 IR；改构造 SSAValue(Ty=Ptr(i64), Name="@coro_pool_<n>") 视图
- ConstNull 签名 (pool, ty, name)，6 处漏传 name → v.Name=None →
  "store i8* (None), i8**" 非法 IR；全部补 "null"

App/lib/core/Gen/AsyncGenMixin.vp

@@ -831,8 +831,14 @@ class AsyncGenMixin(CallGenBase.CallGenBase):
         # M7 帧池：i64 池头（0 = 空）；帧首 8 字节存 next（覆盖 state/done，弹池后统一清零）
         pool_gv: llvmlite.GlobalVariable | t.CPtr = self._get_coro_pool(
             pool, mod, trans, name)
+        # GlobalVariable 非 Value 子类：构造 Value 视图（Ty=Ptr(i64), Name="@coro_pool_<name>"）
+        pool_ref_name: str = pool.alloc(96)
+        if pool_ref_name is not None:
+            viperlib.snprintf(pool_ref_name, 96, "@coro_pool_%s", name)
+        pool_ref: llvmlite.Value | t.CPtr = llvmlite.SSAValue(
+            pool, i64_ptr_ty, pool_ref_name)
         pool_head: llvmlite.Value | t.CPtr = llvmlite.build_load(
-            builder, i64_ty, pool_gv)
+            builder, i64_ty, pool_ref)
         if pool_head is None:
             return 0
         zero64: llvmlite.Value | t.CPtr = llvmlite.const_int64(pool, 0)
@@ -857,7 +863,7 @@ class AsyncGenMixin(CallGenBase.CallGenBase):
             builder, i64_ty, node_next_ptr)
         if next_head is None:
             return 0
-        llvmlite.build_store(builder, next_head, pool_gv)
+        llvmlite.build_store(builder, next_head, pool_ref)
         hit_frame: llvmlite.Value | t.CPtr = llvmlite.build_inttoptr(
             builder, pool_head, frame_ptr_ty)
         if hit_frame is None:
@@ -892,7 +898,7 @@ class AsyncGenMixin(CallGenBase.CallGenBase):
         if frame_ref is None:
             return 0
         zero: llvmlite.Value | t.CPtr = llvmlite.const_int32(pool, 0)
-        null_p: llvmlite.Value | t.CPtr = llvmlite.ConstNull(pool, i8_ptr_ty)
+        null_p: llvmlite.Value | t.CPtr = llvmlite.ConstNull(pool, i8_ptr_ty, "null")
         si: int = 0
         for si in range(5):
             if si == 4:
@@ -2208,15 +2214,21 @@ class AsyncGenMixin(CallGenBase.CallGenBase):
         # 回池：帧首 8 字节存旧池头；池头 = 本帧（i64）
         pool_gv: llvmlite.GlobalVariable | t.CPtr = self._get_coro_pool(
             pool, mod, trans, async_name)
-        pool_head: llvmlite.Value | t.CPtr = llvmlite.build_load(
-            builder, i64_ty, pool_gv)
+        # GlobalVariable 非 Value 子类：构造 Value 视图（Ty=Ptr(i64), Name="@coro_pool_<name>"）
         i64_ptr_ty: llvmlite.LLVMType | t.CPtr = llvmlite.Ptr(pool, i64_ty)
+        pool_ref_name: str = pool.alloc(96)
+        if pool_ref_name is not None:
+            viperlib.snprintf(pool_ref_name, 96, "@coro_pool_%s", async_name)
+        pool_ref: llvmlite.Value | t.CPtr = llvmlite.SSAValue(
+            pool, i64_ptr_ty, pool_ref_name)
+        pool_head: llvmlite.Value | t.CPtr = llvmlite.build_load(
+            builder, i64_ty, pool_ref)
         node_next: llvmlite.Value | t.CPtr = llvmlite.build_bitcast(
             builder, frame_ptr, i64_ptr_ty)
         llvmlite.build_store(builder, pool_head, node_next)
         frame_i64: llvmlite.Value | t.CPtr = llvmlite.build_ptrtoint(
             builder, frame_ptr, i64_ty)
-        llvmlite.build_store(builder, frame_i64, pool_gv)
+        llvmlite.build_store(builder, frame_i64, pool_ref)
         return llvmlite.const_int32(pool, 0)
 
     def translate_coro_exception(self, builder: llvmlite.IRBuilder | t.CPtr,
@@ -2257,23 +2269,23 @@ class AsyncGenMixin(CallGenBase.CallGenBase):
         i8_ptr_ty: llvmlite.LLVMType | t.CPtr = llvmlite.Ptr(
             pool, llvmlite.Int8(pool))
         if cl is None or trans is None or cl.args is None or len(cl.args) < 1:
-            return llvmlite.ConstNull(pool, i8_ptr_ty)
+            return llvmlite.ConstNull(pool, i8_ptr_ty, "null")
         async_name: str = self._var_to_async(trans, cl.args.get(0))
         if async_name is None:
-            return llvmlite.ConstNull(pool, i8_ptr_ty)
+            return llvmlite.ConstNull(pool, i8_ptr_ty, "null")
         frame_ty: llvmlite.LLVMType | t.CPtr = self._lookup_coro_frame(
             trans, async_name)
         if frame_ty is None:
-            return llvmlite.ConstNull(pool, i8_ptr_ty)
+            return llvmlite.ConstNull(pool, i8_ptr_ty, "null")
         frame_ptr_ty: llvmlite.LLVMType | t.CPtr = llvmlite.Ptr(pool, frame_ty)
         frame_val: llvmlite.Value | t.CPtr = self.Gen.ExprGen.translate_value(
             builder, pool, mod, cl.args.get(0), None, 0, trans)
         if frame_val is None:
-            return llvmlite.ConstNull(pool, i8_ptr_ty)
+            return llvmlite.ConstNull(pool, i8_ptr_ty, "null")
         frame_ptr: llvmlite.Value | t.CPtr = llvmlite.build_bitcast(
             builder, frame_val, frame_ptr_ty)
         if frame_ptr is None:
-            return llvmlite.ConstNull(pool, i8_ptr_ty)
+            return llvmlite.ConstNull(pool, i8_ptr_ty, "null")
         msg_ptr: llvmlite.Value | t.CPtr = llvmlite.build_gep_struct(
             builder, frame_ty, i8_ptr_ty, frame_ptr, 4)
         return llvmlite.build_load(builder, i8_ptr_ty, msg_ptr)