Add Python Runner service and documentation

- Introduced a new internal utility service, python-runner, in docker-compose.yml to execute custom Python scripts within the Docker network.
- Added detailed documentation in n8n-installer-developer-guide.md and README.md on how to enable and use the python-runner service.
- Created main.py and requirements.txt files for user-defined Python code and dependencies.
- Updated scripts to include python-runner in the service selection wizard and final report for improved user guidance.

scripts/04_wizard.sh

@@ -66,6 +66,7 @@ base_services_data=(
     "ragapp" "RAGApp (Open-source RAG UI + API)"
     "open-webui" "Open WebUI (ChatGPT-like Interface)"
     "searxng" "SearXNG (Private Metasearch Engine)"
+    "python-runner" "Python Runner (Run your custom Python code from ./python-runner)"
     "ollama" "Ollama (Local LLM Runner - select hardware in next step)"
     "comfyui" "ComfyUI (Node-based Stable Diffusion UI)"
 )

scripts/06_final_report.sh

@@ -187,6 +187,17 @@ if is_profile_active "gotenberg"; then
   echo "  Office to PDF: POST /forms/libreoffice/convert"
 fi
 
+if is_profile_active "python-runner"; then
+  echo
+  echo "================================= Python Runner ========================"
+  echo
+  echo "Internal Container DNS: python-runner"
+  echo "Mounted Code Directory: ./python-runner (host) -> /app (container)"
+  echo "Entry File: /app/main.py"
+  echo "(Note: Internal-only service with no exposed ports; view output via logs)"
+  echo "Logs: docker compose -p localai logs -f python-runner"
+fi
+
 if is_profile_active "n8n" || is_profile_active "langfuse"; then
   echo
   echo "================================= Redis (Valkey) ======================"