feat: MAINT-001 - Fix Ruff violations across all Python source

pyproject.toml

@@ -14,6 +14,11 @@ dev = ["pytest>=8", "openai>=1", "langchain-openai>=0.1", "cryptography>=41"]
 [tool.setuptools]
 packages = []
 
+[tool.ruff]
+# Protobuf/gRPC stubs are regenerated by scripts/generate_native_protocol.py;
+# linting them would drift the checked-in files from the generator's output.
+extend-exclude = ["packages/node/meshnet_node/native_protocol/generated"]
+
 [tool.pytest.ini_options]
 testpaths = ["tests"]
 markers = [