feat(server): refactor provider interface (#11665)

fix AI-4
fix AI-18

better provider/model choose to allow fallback to similar models (e.g., self-hosted) when the provider is not fully configured
split functions of different output types

packages/frontend/admin/src/modules/ai/prompts.tsx

@@ -15,7 +15,6 @@ export type Prompt = {
   action: string | null;
   config: {
     __typename?: 'CopilotPromptConfigType';
-    jsonMode: boolean | null;
     frequencyPenalty: number | null;
     presencePenalty: number | null;
     temperature: number | null;