feat: support gemini-2.0-flash

- Enhance model support by adding new entries and refining checks for system instruction compatibility.
- Update logging display behavior and adjust default quotas for better user experience.
- Revamp pricing structures in the billing system to reflect current model values and deprecate outdated entries.
- Streamline code by replacing hardcoded values with configurations for maintainability.

web/default/src/helpers/utils.js

@@ -224,4 +224,4 @@ export function getChannelModels(type) {
     return channelModels[type];
   }
   return [];
-}
+}