🐛 fix(playbook): address reported repo issues

normalize Windows path-like TOML config values, regenerate .agents/index.md on sync, keep the SKILLS.md superpowers section route-only, and ignore generated Python cache dirs.

add regression coverage for load_config() and the standards sync behavior touched by these fixes.

tests/cli/test_playbook_cli.py

@@ -101,6 +101,46 @@ langs = ["tsl"]
             self.assertEqual(result.returncode, 0)
             self.assertTrue(agents_index.is_file())
 
+    def test_sync_standards_updates_agents_index_when_langs_expand(self):
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            root = Path(tmp_dir)
+
+            first_config = root / "playbook-first.toml"
+            first_config.write_text(
+                f"""
+[playbook]
+project_root = "{tmp_dir}"
+
+[sync_standards]
+langs = ["tsl"]
+no_backup = true
+""",
+                encoding="utf-8",
+            )
+
+            first_result = run_cli("-config", str(first_config))
+            self.assertEqual(first_result.returncode, 0)
+
+            second_config = root / "playbook-second.toml"
+            second_config.write_text(
+                f"""
+[playbook]
+project_root = "{tmp_dir}"
+
+[sync_standards]
+langs = ["tsl", "cpp"]
+no_backup = true
+""",
+                encoding="utf-8",
+            )
+
+            second_result = run_cli("-config", str(second_config))
+            self.assertEqual(second_result.returncode, 0)
+
+            agents_index = (root / ".agents" / "index.md").read_text(encoding="utf-8")
+            self.assertIn("`.agents/tsl/index.md`", agents_index)
+            self.assertIn("`.agents/cpp/index.md`", agents_index)
+
     def test_sync_standards_agents_block_has_blank_lines(self):
         with tempfile.TemporaryDirectory() as tmp_dir:
             config_body = f"""