refactor: use processor in infer backup

[wooway777]

Summary

• 在infer backup中使用processor

Motivation

目前的test infer经过了LLM，有concern说涉及的东西太多了。所以更新备份的单请求入口使用新的基建，后续可能会二选一

Closes #367

Type of Change

• feat — new feature / new model
• fix — bug fix
• perf — performance improvement (no behavioral change)
• refactor — code restructuring without behavior change
• test — adding or fixing tests only
• docs — documentation only
• build / ci — build system or CI configuration
• chore — tooling, formatting, or other non-code changes
• Breaking change

Test Results of Involved Models on Supported Platforms (Please attach screenshots)

Benchmark / Performance Impact

Notes for Reviewers

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