fix(e2b): count and warn on malformed porcelain records (#967)

Both reviewers caught the same leftover: `_parse_porcelain`'s `rejected`
counter was never incremented. Deleting the C-unquoter removed the only
thing that incremented it, and I left the variable and its docstring
claim behind — so a malformed record was silently dropped, contradicting
this PR's own "never silently dropped" framing for AC2.

Real git cannot emit a record that isn't "XY PATH", so a malformed one
means the sandbox's git is not git — precisely the case worth surfacing.
Now warned, counted, and folded into the count emitted to the user
alongside containment rejections.

Author: frankbria

codeframe/adapters/e2b/adapter.py

@@ -396,6 +396,10 @@ def _parse_porcelain(stdout: str) -> tuple[list[str], int]:
             index += 1
             # "XY PATH" — exactly two status characters and a space.
             if len(entry) < 4 or entry[2] != " ":
+                # Counted and warned, not dropped: real git cannot emit this,
+                # so a malformed record means the sandbox's git is not git.
+                rejected += 1
+                logger.warning("Rejected malformed porcelain record: %r", entry)
                 continue
             status, raw = entry[:2], entry[3:]
 

tests/adapters/test_e2b_trust_boundary_967.py

@@ -245,6 +245,37 @@ def test_a_filename_containing_the_rename_arrow_is_not_mangled(self, workspace):
         files, _ = adapter._download_changed_files(sbx, workspace, lambda *a, **k: None)
         assert files == ["a -> b.py"]
 
+    def test_a_malformed_record_is_counted_and_warned_not_dropped(self, workspace, caplog):
+        """AC2 applies to parse rejections too, not just containment ones."""
+        import logging
+
+        with caplog.at_level(logging.WARNING):
+            files, count = _download(_sbx("xx", " M ok.py", content="x"), workspace)
+
+        assert files == ["ok.py"]
+        assert count == 1
+        assert any("xx" in r.getMessage() for r in caplog.records), caplog.text
+
+    def test_the_parse_reject_count_reaches_the_user(self, workspace):
+        from codeframe.adapters.e2b.adapter import E2BAgentAdapter
+
+        emitted: list[str] = []
+        E2BAgentAdapter(timeout_minutes=5)._download_changed_files(
+            _sbx("xx", "y", " M ../outside", content="x"),
+            workspace,
+            lambda kind, msg, *a: emitted.append(msg),
+        )
+        # 2 unparseable + 1 escaping the workspace
+        assert any("3" in m and "reject" in m.lower() for m in emitted), emitted
+
+    def test_parse_rejects_are_reported_separately_from_containment(self):
+        """_parse_porcelain's own return value must mean something."""
+        from codeframe.adapters.e2b.adapter import E2BAgentAdapter
+
+        paths, rejected = E2BAgentAdapter._parse_porcelain("xx\0 M ok.py\0y\0")
+        assert paths == ["ok.py"]
+        assert rejected == 2
+
     def test_porcelain_is_requested_nul_separated(self, workspace):
         """-z is what removes the separator ambiguity above."""
         sbx = _sbx(" M ok.py", content="x")