[core] upgrade grpc to v1.76.0

[rueian]

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Description

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Related issues

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[gemini-code-assist]

Code Review

This pull request upgrades gRPC to v1.76.0 and updates related dependencies like protobuf and boringssl. The security review noted that no specific code changes were provided for analysis, thus a detailed security review could not be performed. The code review identified areas for improvement within the patch file to enhance code clarity and correctness, specifically regarding the adaptation of the configurable gRPC thread count for the new gRPC version.

[gemini-code-assist]

The code uses std::strlen on line 21, which requires the <cstring> header. This header is not included in the patch, which may lead to compilation errors. Please add #include <cstring> to ensure std::strlen is available.

#include <cstdlib>
#include <cstring>