Use SafeUnpickler

[yiliu30]

Type of Change

feature or bug fix or documentation or validation or others
API changed or not

Description

detail description

Expected Behavior & Potential Risk

the expected behavior that triggered by this PR

How has this PR been tested?

how to reproduce the test (including hardware information)

Dependency Change?

any library dependency introduced or removed

[Copilot]

Pull Request Overview

This PR introduces a security improvement by replacing the unsafe pickle.load() with a custom SafeUnpickler class to prevent arbitrary code execution during deserialization of tuning history files.

• Implements a custom SafeUnpickler class with restricted class loading
• Replaces direct pickle.load() usage with the safer alternative
• Adds necessary imports for builtins and OrderedDict

[yiliu30]

@chensuyue @XuehaoSun
The CI failed due to the issue below. Can we get it merged first?

2025-07-21T11:05:58.8719458Z Installing collected packages: protobuf
2025-07-21T11:05:58.8719820Z   Attempting uninstall: protobuf
2025-07-21T11:05:58.8720027Z     Found existing installation: protobuf 3.19.6
2025-07-21T11:05:58.8757317Z     Uninstalling protobuf-3.19.6:
2025-07-21T11:05:59.0170443Z       Successfully uninstalled protobuf-3.19.6
2025-07-21T11:05:59.1161078Z ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
2025-07-21T11:05:59.1161556Z tensorboard 2.10.1 requires protobuf<3.20,>=3.9.2, but you have protobuf 3.20.3 which is incompatible.
2025-07-21T11:05:59.1161810Z tensorflow 2.11.dev202323 requires protobuf<3.20,>=3.9.2, but you have protobuf 3.20.3 which is incompatible.