fix: [PrefEval Evaluation] propagate --lib and --version arguments in search and response modes

[fancyboi999]

Description

Summary:
Fixed a bug in the run_prefeval_eval.sh script where the --lib and --version arguments were not being propagated to the Python scripts (pref_*.py) during the search and response modes.

Previously, these arguments were only passed during the add mode. This caused the scripts to fallback to default values (e.g., lib="supermemory", version="0929-1") in subsequent steps, leading to incorrect file path resolutions or execution errors when non-default configurations were used. This change ensures consistent argument passing across all pipeline stages.

Fix: #764

Docs Issue/PR: N/A

Reviewer: @fridayL @CaralHsi

Checklist:

• I have performed a self-review of my own code | 我已自行检查了自己的代码
• I have commented my code in hard-to-understand areas | 我已在难以理解的地方对代码进行了注释
• I have added tests that prove my fix is effective or that my feature works | 我已添加测试以证明我的修复有效或功能正常
• I have created related documentation issue/PR in MemOS-Docs (if applicable) | 我已在 MemOS-Docs 中创建了相关的文档 issue/PR（如果适用）
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