chore(config): configure LLM provider and cost limits

.env.example

@@ -24,6 +24,15 @@ SurrealDb__DataDirectory=data
 # LLM (F-8, matchmaking) — runtime secret only.
 # LLM__ApiKey=
 
+# LLM provider/cost control (optional; disabled by default -> offline template rationales).
+# Llm__Enabled=false
+# Llm__Provider=openai
+# Llm__BaseUrl=https://api.openai.com/v1
+# Llm__Model=gpt-4o-mini
+# Llm__MaxTokens=256
+# Llm__MaxRequestsPerMinute=30
+# Llm__TimeoutSeconds=20
+
 # Observability (optional).
 # Logging__LogLevel__Default=Information
 # OTEL_EXPORTER_OTLP_ENDPOINT=

backend/appsettings.json

@@ -11,6 +11,15 @@
     "Audience": "tarninahub",
     "TokenLifetimeMinutes": 60
   },
+  "Llm": {
+    "Enabled": false,
+    "Provider": "openai",
+    "BaseUrl": "https://api.openai.com/v1",
+    "Model": "gpt-4o-mini",
+    "MaxTokens": 256,
+    "MaxRequestsPerMinute": 30,
+    "TimeoutSeconds": 20
+  },
   "SurrealDb": {
     "Namespace": "hubmi",
     "Database": "hubmi",