fix: Export ToolOperationSchema and ToolOperation from models index

- Add ToolOperationSchema to runtime schema exports
- Add ToolOperation to type-only exports
- Fixes TypeScript test imports in CI/CD Pipeline
- Resolves "Cannot read properties of undefined (reading 'safeParse')" error

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: alicoding

packages/core/src/models/index.ts

@@ -18,6 +18,7 @@ export {
   ConversationSchema,
   MessageCategorySchema,
   MessageGroupSchema,
+  ToolOperationSchema,
 
   // Enums (runtime constants)
   MessageTypeEnum,
@@ -42,6 +43,7 @@ export type {
   Conversation,
   MessageCategory,
   MessageGroup,
+  ToolOperation,
 
   // Enum types
   MessageType,