ISSUE-171: upgrade grpc to 1.40

[jingyichen1223]

Key Changes

1. Dependencies Version Upgrade

• gRPC: 1.16.1 -> 1.40.0
• abseil-cpp: 20190808 -> 20210324.0 (LTS release bundled with gRPC 1.40)

2. Abseil-cpp Dependency Refactoring

Before: abseil-cpp was managed as a git submodule of Gringofts. Gringofts and gRPC both has their own Abseil-cpp. Abseil is compiled separately for both, and are linked together at last.
After: abseil-cpp (version 20210324.0) is installed system-wide and shared across both gRPC and Gringofts. It is only compiled and installed once.
(If don't do so, 20210324.0 abseil in Gringofts and gRPC have symbol conflict)

3. Symbol Conflict Resolution

Problem: gRPC 1.40 exposes abseil symbols, which could conflict with Gringoft's abseil symbols when linking executables

Solution:

• Configure abseil to use C++17 standard library types (std::string_view, std::optional, etc.) instead of abseil's own types
• Compile both gRPC and abseil with consistent C++17 settings
• Use gRPC_ABSL_PROVIDER=package to ensure gRPC links against system-installed abseil
• This ensures type consistency across all components and eliminates symbol conflicts

[Copilot]

Pull request overview

This PR upgrades gRPC from version 1.16.1 to 1.40.0 and refactors the abseil-cpp dependency management to address symbol conflicts. The key architectural change is moving abseil-cpp from a git submodule to a system-wide installation shared between gRPC and Gringofts, compiled with C++17 to ensure ABI compatibility and use of standard library types.

Changes:

• Upgraded gRPC to 1.40.0 and abseil-cpp to 20210324.0 LTS release
• Removed abseil-cpp git submodule and implemented system-wide installation
• Updated build scripts to compile both gRPC and abseil-cpp with C++17 standard and consistent compiler flags

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
scripts/installDependencies.sh	Added system-wide abseil-cpp installation with C++17 and SIGSTKSZ fix; updated gRPC installation to use system abseil package
scripts/downloadDependencies.sh	Updated gRPC version to 1.40.0 and CMake download URL to GitHub
scripts/addSubmodules.sh	Removed abseil-cpp submodule initialization
CMakeLists.txt	Changed from submodule to system abseil via find_package(); removed submodule include path
dockers/dependencies/install.Dockerfile	Updated Docker image tag from v3 to v4
dockers/dependencies/download.Dockerfile	Updated Docker image tag from v3 to v4
README.md	Updated Docker image references from v3 to v4; removed abseil-cpp from third-party license section
.github/workflows/main.yml	Updated CI workflow to use v4 Docker image

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[jingyichen1223]

gRPC1.40 in this compile image has performance degradation, so close this PR