fix(gen): 模块前言 C 库声明名改落 PermPool，避免被回绕的模块池覆盖

现象：@malloc 的声明名被渲染成乱码，mlir-opt 报 llvm.call @malloc does not reference a symbol in the current scope。根因：create_declare 用 _str_dup(pool, name) 把名字拷进传入的池，而前言用的是模块池（大模块上会被复用/回绕），早期分配的声明名被后续分配覆盖；类型是 mlirlite 内部 interned 的，所以只有名字坏、参数类型正常。修法：声明与参数名改落 CompilerFactory.PermPool（never reset）。

App/lib/core/Gen/Translator.vp

@@ -10,6 +10,7 @@ import stdio
 import stdlib
 import viperlib
 import lib.core.VLogger as VLogger
+import lib.core.CompilerFactory as CompilerFactory
 import lib.Projectrans.Config as Config
 import lib.Stub.StubMerger.StubMergerBuild as StubMergerBuild
 import lib.Stub.StubMerger.StubMergerStore as StubMergerStore
@@ -413,34 +414,43 @@ novirtual class Translator:
         i8_ty: mlirlite.LLVMType* = mlirlite.Int8(pool)
         i8_ptr_ty: mlirlite.LLVMType* = mlirlite.Ptr(pool, i8_ty)
 
+        # 模块前言里 C 库声明的**名字**必须落在 PermPool：create_declare 会 _str_dup(pool, name)
+        # 把名字拷进传入的池，而本模块池（trans.Pool）在大模块上会被复用/回绕，覆盖早期分配 →
+        # 名字悬空（现场：@malloc 被渲染成乱码 @"PL\xEF\xBF\xBDp…"，mlir-opt 报
+        #  "'llvm.call' op 'malloc' does not reference a symbol in the current scope"；
+        #  类型是 mlirlite 内部 interned 的，所以只有名字坏、参数类型正常）。
+        # PermPool 是"persistent data; never reset"，正好符合声明名的生命周期。
+        decl_pool: memhub.MemBuddy* = CompilerFactory.factory.PermPool
+        if decl_pool is None: decl_pool = pool
+
         # Declare printf
-        printf_func: mlirlite.Function* = mlirlite.create_declare(pool, mod, "printf", i32_ty)
+        printf_func: mlirlite.Function* = mlirlite.create_declare(decl_pool, mod, "printf", i32_ty)
         if printf_func is None:
             VLogger.error("CreateDeclare printf returned NULL", "TR")
             return 1
-        mlirlite.add_param(pool, printf_func, i8_ptr_ty, "fmt")
+        mlirlite.add_param(decl_pool, printf_func, i8_ptr_ty, "fmt")
         printf_func.IsVarArg = 1
         # Declare LLVM va_start/va_end intrinsics (used inside *args function bodies):
         # declare void @llvm.va_start(i8*) / declare void @llvm.va_end(i8*)
         void_ty_decl: mlirlite.LLVMType* = mlirlite.Void(pool)
-        va_start_func: mlirlite.Function* = mlirlite.create_declare(pool, mod, "llvm.va_start", void_ty_decl)
-        if va_start_func is not None: mlirlite.add_param(pool, va_start_func, i8_ptr_ty, "ap")
-        va_end_func: mlirlite.Function* = mlirlite.create_declare(pool, mod, "llvm.va_end", void_ty_decl)
-        if va_end_func is not None: mlirlite.add_param(pool, va_end_func, i8_ptr_ty, "ap")
+        va_start_func: mlirlite.Function* = mlirlite.create_declare(decl_pool, mod, "llvm.va_start", void_ty_decl)
+        if va_start_func is not None: mlirlite.add_param(decl_pool, va_start_func, i8_ptr_ty, "ap")
+        va_end_func: mlirlite.Function* = mlirlite.create_declare(decl_pool, mod, "llvm.va_end", void_ty_decl)
+        if va_end_func is not None: mlirlite.add_param(decl_pool, va_end_func, i8_ptr_ty, "ap")
 
         # Declare malloc (for closure allocation)
-        malloc_func: mlirlite.Function* = mlirlite.create_declare(pool, mod, "malloc", i8_ptr_ty)
+        malloc_func: mlirlite.Function* = mlirlite.create_declare(decl_pool, mod, "malloc", i8_ptr_ty)
         if malloc_func is not None:
             i64_ty: mlirlite.LLVMType* = mlirlite.Int64(pool)
-            mlirlite.add_param(pool, malloc_func, i64_ty, "size")
+            mlirlite.add_param(decl_pool, malloc_func, i64_ty, "size")
 
         # Declare free (counterpart of malloc): M3 owned slife 的出口释放要用它。
         # 必须在这里（模块前言）声明：释放点只做**查表 + fail-fast**（VarGenMixin._SlifeEmitGuardedFree），不再现场建 declare——
         # 否则同一模块的每个出口各建一份重复 declare。缺了它 mlir-opt 会报
         # "'llvm.call' op 'free' does not reference a symbol in the current scope"
         # （现场：Test/NewLifetimeTest 未 import stdlib，拿不到 stdlib vpi 的 declare）。
-        free_func: mlirlite.Function* = mlirlite.create_declare(pool, mod, "free", void_ty_decl)
-        if free_func is not None: mlirlite.add_param(pool, free_func, i8_ptr_ty, "p")
+        free_func: mlirlite.Function* = mlirlite.create_declare(decl_pool, mod, "free", void_ty_decl)
+        if free_func is not None: mlirlite.add_param(decl_pool, free_func, i8_ptr_ty, "p")
 
         # Check whether the user defined a main function
         has_user_main: int = 0