feat(core): add optionalModels field in AiPrompt and support the front-end modelId param (#12224)

Close [AI-116](https://linear.app/affine-design/issue/AI-116)

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit

- **New Features**
  - Added support for specifying alternative AI models in chat prompts, enabling users to select from multiple available models.
  - Expanded AI model options with new additions: 'gpt-4.1', 'o3', and 'claude-3-5-sonnet-20241022'.

- **Enhancements**
  - Users can now optionally choose a specific AI model during chat interactions.
  - Prompts and chat sessions reflect and support selection of alternative models where applicable.

- **Bug Fixes**
  - Improved handling of prompt configuration defaults for better reliability.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/backend/server/schema.prisma

@@ -397,6 +397,7 @@ model AiPrompt {
   // it is only used in the frontend and does not affect the backend
   action    String?  @db.VarChar
   model     String   @db.VarChar
+  optionalModels String[] @default([]) @db.VarChar @map("optional_models")
   config    Json?    @db.Json
   createdAt DateTime @default(now()) @map("created_at") @db.Timestamptz(3)
   updatedAt DateTime @default(now()) @map("updated_at") @db.Timestamptz(3)