chore: bump version to 4.3.0

Full feature parity release - all 42 SDKs now implement:
- Complete API coverage (58+ functions matching un.h spec)
- HTTP 428 sudo OTP challenge handling
- Comprehensive unit, integration, and functional tests

clients/python/sync/setup.py

@@ -7,7 +7,7 @@ with open("README.md", "r", encoding="utf-8") as fh:
 
 setup(
     name="unsandbox",
-    version="4.2.50",
+    version="4.3.0",
     author="Unsandbox",
     description="Synchronous Python SDK for unsandbox.com code execution",
     long_description=long_description,