test: isolate CLI output capture with monkeypatch/redirect to fix stdout corruption in full suite runs (Issue #178)

- Replace raw patch("sys.stdout") and contextlib.redirect_stderr with pytest MonkeyPatch or contextlib redirect scoped to main calls in CLI tests (create_*, prs, python_cli, manage_labels, merge_pr, review_pr).
- Add regression tests in test_review_proofs.py for stdout/stderr remaining usable.
- Ensures normal pytest summary output without junitxml workaround; improves review validation reporting per #173.
- No behavior change to production code or gates.

Refs #178

tests/test_create_issue.py

@@ -11,6 +11,7 @@ import json
 import sys
 import tempfile
 import unittest
+import contextlib
 from unittest.mock import MagicMock, patch
 
 # The module under test lives in the repo root, not a package.
@@ -38,7 +39,8 @@ class TestArgParsing(unittest.TestCase):
     @patch("create_issue.api_request", return_value={"number": 1, "html_url": "http://x/1"})
     @patch("create_issue.get_credentials", return_value=FAKE_CREDS)
     def test_minimal_args(self, _cred, _api):
-        rc = create_issue.main(["--title", "Hello"])
+        with contextlib.redirect_stdout(io.StringIO()), contextlib.redirect_stderr(io.StringIO()):
+            rc = create_issue.main(["--title", "Hello"])
         self.assertEqual(rc, 0)
 
     def test_missing_title_exits(self):
@@ -50,7 +52,8 @@ class TestArgParsing(unittest.TestCase):
     @patch("create_issue.get_credentials", return_value=FAKE_CREDS)
     def test_remote_choices(self, _cred, _api):
         for remote in ("dadeschools", "prgs"):
-            rc = create_issue.main(["--remote", remote, "--title", "X"])
+            with contextlib.redirect_stdout(io.StringIO()), contextlib.redirect_stderr(io.StringIO()):
+                rc = create_issue.main(["--remote", remote, "--title", "X"])
             self.assertEqual(rc, 0, f"--remote {remote} should be accepted")
 
     def test_invalid_remote_exits(self):
@@ -138,7 +141,8 @@ class TestAuthFailure(unittest.TestCase):
 
     @patch("create_issue.get_credentials", return_value=("", ""))
     def test_no_credentials_returns_1(self, _cred):
-        rc = create_issue.main(["--title", "T"])
+        with contextlib.redirect_stdout(io.StringIO()), contextlib.redirect_stderr(io.StringIO()):
+            rc = create_issue.main(["--title", "T"])
         self.assertEqual(rc, 1)
 
 
@@ -152,7 +156,8 @@ class TestAPIError(unittest.TestCase):
     def test_api_error_returns_1(self, _cred):
         with patch("create_issue.api_request",
                    side_effect=RuntimeError("HTTP 422: duplicate")):
-            rc = create_issue.main(["--title", "Dup"])
+            with contextlib.redirect_stdout(io.StringIO()), contextlib.redirect_stderr(io.StringIO()):
+                rc = create_issue.main(["--title", "Dup"])
             self.assertEqual(rc, 1)