fix(hub): ship temperature override OFF by default

The default Resources/CoreAISettings asset had enableTemperatureOverriding=1, so
the Hub's 'Override temperature' toggle showed ON out of the box even though the code
default (and every other settings asset) is OFF. Flip it to 0 so a fresh Hub uses each
backend's own default sampling temperature.

Author: NeoXider

Assets/Resources/CoreAISettings.asset

@@ -19,7 +19,7 @@ MonoBehaviour:
   apiKey: lm-studio
   modelName: qwen3.5-4b-mtp
   visionSupport: 0
-  enableTemperatureOverriding: 1
+  enableTemperatureOverriding: 0
   temperature: 0.2
   enableMaxTokensOverriding: 0
   maxTokens: 128000