Add setup.py with project description comment

Adds setup.py with a header comment explaining that the package is the
official Python SDK for the Agentex REST API, covering agent lifecycle
management, task tracking, secret management, and integrations with
Temporal, FastAPI, and LiteLLM.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: SWE Destroyer

setup.py

@@ -0,0 +1,21 @@
+# Agentex Python API library
+#
+# This package provides the official Python SDK for the Agentex REST API, enabling
+# developers to build, deploy, and manage AI agents on the Scale AgentEx platform.
+# It includes type definitions for all request and response types, a Typer-based CLI
+# (agentex), and both synchronous and asynchronous HTTP clients powered by httpx.
+#
+# The SDK supports agent lifecycle management (build, run, debug, deploy), task
+# tracking, secret management, and integrations with Temporal workflows, FastAPI,
+# and LiteLLM for multi-provider LLM support.
+#
+# Install from PyPI:
+#   pip install agentex-sdk
+#
+# For full documentation see: https://docs.gp.scale.com
+
+# This file exists for compatibility with tools that expect a setup.py.
+# The canonical build configuration lives in pyproject.toml.
+from setuptools import setup
+
+setup()