feat: add .env.example for all

src/open-webui/.env.example

@@ -1,4 +1,15 @@
-OPENAI_API_BASE_URL=
+# Open WebUI Version
+OPEN_WEBUI_VERSION=main
+
+# Port to bind to on the host machine
+OPEN_WEBUI_PORT=8080
+
+# OpenAI API Configuration (optional)
+OPENAI_API_BASE_URL=https://api.openai.com/v1
 OPENAI_API_KEY=
-ENABLE_OLLAMA_API=
+
+# Enable Ollama API integration (default: true)
+ENABLE_OLLAMA_API=true
+
+# WebUI URL (optional, for external access configuration)
 WEBUI_URL=