Break tool config schema import cycle

tests/config/test_tool_config_boundaries.py

@@ -0,0 +1,38 @@
+import ast
+import subprocess
+import sys
+from pathlib import Path
+
+
+def test_config_base_import_does_not_load_config_schema():
+    code = """
+import sys
+from nanobot.config_base import Base
+print("nanobot.config.schema" in sys.modules)
+"""
+    result = subprocess.run(
+        [sys.executable, "-c", code],
+        check=True,
+        capture_output=True,
+        text=True,
+    )
+
+    assert result.stdout.strip() == "False"
+
+
+def test_builtin_tool_configs_do_not_depend_on_config_schema_base():
+    repo = Path(__file__).resolve().parents[2]
+    tool_paths = sorted((repo / "nanobot/agent/tools").glob("*.py"))
+
+    violations = []
+    for path in tool_paths:
+        tree = ast.parse(path.read_text(encoding="utf-8"))
+        for node in ast.walk(tree):
+            if not isinstance(node, ast.ImportFrom):
+                continue
+            if node.module != "nanobot.config.schema":
+                continue
+            if any(alias.name == "Base" for alias in node.names):
+                violations.append(str(path.relative_to(repo)))
+
+    assert violations == []