✨ feat(playbook): add no_backup deploy controls

remove obsolete main_language placeholders and language summary template text

limit generated .agents guidance to configured langs and normalize AGENT_RULES trailing newlines

document install_skills no_backup behavior and refresh tests for deployment links and sync flows

tests/cli/test_playbook_cli.py

@@ -237,6 +237,29 @@ no_backup = true
             self.assertIn("`.agents/tsl/index.md`", agents_index)
             self.assertIn("`.agents/cpp/index.md`", agents_index)
 
+    def test_sync_standards_agents_index_only_lists_configured_langs(self):
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            root = Path(tmp_dir)
+            config_body = f"""
+[playbook]
+project_root = "{tmp_dir}"
+deploy_root = "{CUSTOM_DEPLOY_ROOT}"
+
+[sync_standards]
+langs = ["tsl", "markdown"]
+"""
+            config_path = write_config(root, "playbook.toml", config_body)
+
+            result = run_cli("-config", str(config_path))
+            self.assertEqual(result.returncode, 0, msg=result.stdout + result.stderr)
+
+            agents_index = (root / ".agents" / "index.md").read_text(encoding="utf-8")
+            self.assertIn("`.agents/tsl/`：TSL 相关规则集", agents_index)
+            self.assertIn("`.agents/markdown/`：Markdown 相关规则集", agents_index)
+            self.assertNotIn("`.agents/cpp/`", agents_index)
+            self.assertNotIn("`.agents/python/`", agents_index)
+            self.assertNotIn("`.agents/typescript/`", agents_index)
+
     def test_sync_standards_agents_block_has_blank_lines(self):
         with tempfile.TemporaryDirectory() as tmp_dir:
             config_body = f"""