test(pbls): 新增 scripts/dspy_shell_scan.py —— .dspy 空壳/无return/return在async with内 静态扫描（QC 退回 #5 自检口径落地）

QC #5 指出「纯注释文件同样能通过 ast 解析，ast OK 不构成修复在位证据」。
本脚本把自检口径改为可机械核验三项：非注释可执行语句数>0（ast stmt 计数）、
显式 return 数>0 且不在 async with 块内、ast 包装语法通过。
实测：apps/pbls+modules/pbls 6 个 .dspy violations=0；
扩扫 15 个 pbl_* 自研模块 + 9 个复用模块共 156 个 .dspy，violations=2
（modules/world 两处 return 在 async with 内，属 referenced_modules 写保护范围，
 且两文件均有块外 return result 兜底不会返回 None，仅记录不修改）。

scripts/dspy_shell_scan.py

@@ -0,0 +1,92 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+.dspy 空壳/语法/return 静态扫描（QC 退回 #5 要求的自检口径）
+
+背景：Bug WIu0Rkn0KwB0XTjYZz0qk 的 QC 退回意见 #5 指出——「纯注释文件同样能通过
+ast 解析，ast OK 不构成『修复在位』证据」。本脚本把自检口径改为可机械核验的三项：
+  1) 非注释可执行语句数 > 0（ast 统计 stmt 节点，排除包装函数本身）
+  2) 显式 return 数 > 0（ast.Return 计数），且 return 不落在 async with 块内
+  3) ast 包装（async def 包裹）语法解析通过
+
+用法：
+    python3 scripts/dspy_shell_scan.py [root ...]
+缺省 root = apps modules（相对机构工作空间根）。退出码：0=全通过，1=存在违规。
+"""
+import ast
+import os
+import sys
+
+SKIP_PARTS = {".git", "venv", ".pylibs", "node_modules", "__pycache__", "wheelhouse"}
+
+
+def scan_file(path):
+    """返回 (ok, reason, metrics)"""
+    try:
+        with open(path, encoding="utf-8", errors="replace") as fh:
+            src = fh.read()
+    except Exception as exc:  # pragma: no cover
+        return False, "READ_FAIL %s" % exc, {}
+
+    wrapped = "async def _h():\n" + "".join("    " + ln + "\n" for ln in src.split("\n"))
+    try:
+        tree = ast.parse(wrapped)
+    except SyntaxError as exc:
+        return False, "AST_FAIL %s" % exc, {"bytes": len(src.encode("utf-8"))}
+
+    stmts = 0
+    returns = 0
+    for node in ast.walk(tree):
+        if isinstance(node, ast.stmt) and not isinstance(
+            node, (ast.FunctionDef, ast.AsyncFunctionDef)
+        ):
+            stmts += 1
+        if isinstance(node, ast.Return):
+            returns += 1
+
+    ret_in_asyncwith = []
+    for node in ast.walk(tree):
+        if isinstance(node, ast.AsyncWith):
+            for sub in ast.walk(node):
+                if isinstance(sub, ast.Return):
+                    ret_in_asyncwith.append(sub.lineno)
+
+    metrics = {
+        "bytes": len(src.encode("utf-8")),
+        "ast_stmts": stmts,
+        "ast_return": returns,
+        "return_in_asyncwith": ret_in_asyncwith,
+    }
+    if stmts == 0:
+        return False, "SHELL_ONLY: 0 executable statements", metrics
+    if returns == 0:
+        return False, "NO_RETURN: stmts=%d returns=0" % stmts, metrics
+    if ret_in_asyncwith:
+        return False, "RETURN_INSIDE_ASYNC_WITH lines=%s" % ret_in_asyncwith, metrics
+    return True, "OK", metrics
+
+
+def main(argv):
+    roots = argv[1:] or ["apps", "modules"]
+    total = 0
+    bad = []
+    for root in roots:
+        for dirpath, dirnames, filenames in os.walk(root):
+            dirnames[:] = [d for d in dirnames if d not in SKIP_PARTS]
+            for name in filenames:
+                if not name.endswith(".dspy"):
+                    continue
+                path = os.path.join(dirpath, name)
+                total += 1
+                ok, reason, metrics = scan_file(path)
+                if not ok:
+                    bad.append((path, reason, metrics))
+    print("scanned .dspy files: %d" % total)
+    print("violations: %d" % len(bad))
+    for path, reason, metrics in bad:
+        print("  %s -> %s | %s" % (path, reason, metrics))
+    return 1 if bad else 0
+
+
+if __name__ == "__main__":
+    sys.exit(main(sys.argv))