update: add ruff and pytest config in pyproject.toml

pyproject.toml

@@ -20,3 +20,13 @@ backend-path = ["."]
 
 [tool.uv]
 package = true
+
+[tool.ruff]
+line-length = 88
+target-version = "py313"
+
+[tool.ruff.lint]
+select = ["E", "F", "I", "B", "UP"]
+
+[tool.pytest.ini_options]
+testpaths = ["tests"]