fix(langgraph): bump Python langgraph version to 1.1.5

langgraph-prebuilt 1.0.9 imports ExecutionInfo and ServerInfo from
langgraph.runtime, which only exist in langgraph>=1.1.5. Pinning to
1.0.7 causes an ImportError at runtime (langchain-ai/langgraph#7404).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ericapisani

src/runner/templates/agents/python/langgraph/config.json

@@ -14,6 +14,6 @@
       "version": "latest"
     }
   ],
-  "versions": ["1.0.7"],
+  "versions": ["1.1.5"],
   "sentryVersions": ["latest"]
 }