chore(dbg): 给 NLL 谓词插桩（[NLL-ST] 逐条语句 + [NLL-UNSAFE]/[NLL-MENTION] 拒绝原因），定位后删除

App/lib/core/Gen/StructGenMixin.vp

@@ -781,6 +781,8 @@ novirtual class StructGenMixin:
             return self._NllListMentions(ast.Tuple*(node).elts, al)
         ch: list[ast.AST*]* = node.children
         if ch is not None: return self._NllListMentions(ch, al)
+        # 【临时诊断】认不出的种类被判"提及"
+        VLogger.info(f"[NLL-MENTION] unknown kind={k} line={node.lineno}", "NLL")
         return 1     # 认不出的种类：保守算"提及"
 
     def _NllAliasSource(self, value: ast.AST*, al: sizet*) -> int:
@@ -843,8 +845,12 @@ novirtual class StructGenMixin:
                 if a is None or a.kind() != ast.ASTKind.Name: continue
                 an: ast.Name* = ast.Name*(a)
                 if an.id is None or self._NllInSet(al, an.id) == 0: continue
-                if mask < 0: return 1
-                if ((mask >> idx) & 1) != 0: return 1
+                if mask < 0:
+                    VLogger.info(f"[NLL-UNSAFE] arg-mask-unknown line={node.lineno}", "NLL")
+                    return 1
+                if ((mask >> idx) & 1) != 0:
+                    VLogger.info(f"[NLL-UNSAFE] arg-escapes bit={idx} line={node.lineno}", "NLL")
+                    return 1
             return 0
         if k == ast.ASTKind.New:
             # 构造实参里的调用同样要按不安全位置检查
@@ -866,6 +872,8 @@ novirtual class StructGenMixin:
             return self._NllExprUnsafe(ie.orelse, al)
         ch: list[ast.AST*]* = node.children
         if ch is not None: return self._NllListUnsafe(ch, al)
+        # 【临时诊断】认不出的表达式种类
+        VLogger.info(f"[NLL-UNSAFE] unknown-expr kind={k} line={node.lineno}", "NLL")
         return 1     # 认不出的表达式种类：保守按"不安全"处理
 
     def _NllStmts(self, stmts: list[ast.AST*]*, al: sizet*, def_node: ast.AST*, depth: int) -> int:
@@ -881,6 +889,8 @@ novirtual class StructGenMixin:
             i += 1
             if st is None: continue
             k: int = st.kind()
+            # 【临时诊断：定位 NLL 拒绝点，定位后删除】
+            VLogger.info(f"[NLL-ST] line={st.lineno} kind={k}", "NLL")
             if k == ast.ASTKind.Return:
                 if self._NllMentions(ast.Return*(st).value, al) != 0: return 0
             elif k == ast.ASTKind.Assign: