feat: implement automatic format inference service with candidate generation and prediction model

- Add formatCandidateRules.ts to define rules for generating format candidates based on file features.
- Introduce formatPredictionModel.ts to predict the most likely target format based on user behavior and file features.
- Create inferenceService.ts to integrate all inference modules and provide a unified inference API.
- Develop inference.tsx as an API endpoint for frontend calls to predict formats and engines based on file extensions.
- Implement logging for conversion events and dismissals, along with user profile retrieval.
- Ensure warmup management for engine predictions and provide status checks.

README.md

@@ -19,6 +19,7 @@
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