Update Python version to 3.11 and upgrade dependencies

Switched Python version specification from 3.13.7 to 3.11.0 in render.yaml and added .python-version file. Updated langchain-related dependencies in requirements.txt to newer versions. Removed runtime.txt in favor of .python-version for Python version management.

Author: ThomasJButler

.python-version

@@ -0,0 +1 @@
+3.11

backend/requirements.txt

@@ -1,8 +1,8 @@
 fastapi==0.104.1
 uvicorn[standard]==0.24.0
-langchain==0.1.17
-langchain-openai==0.1.8
-langchain-community==0.0.38
+langchain==0.2.16
+langchain-openai==0.1.25
+langchain-community==0.2.17
 chromadb==0.4.24
 python-dotenv==1.0.0
 pydantic==2.5.3

render.yaml

@@ -10,7 +10,7 @@ services:
     healthCheckPath: /health
     envVars:
       - key: PYTHON_VERSION
-        value: 3.13.7
+        value: 3.11.0
       - key: PORT
         generateValue: true
       - key: OPENAI_API_KEY