Add test to weak-node-api

[kraenhansen]

Stacked on #320.

Merging this PR will:

• Add a tests directory in the weak-node-api package with two trivial tests using catch2.

[Copilot]

Pull Request Overview

This PR adds C++ unit tests to the weak-node-api package using the Catch2 testing framework. The tests verify the weak API injection mechanism and function call propagation.

Key changes:

• Introduces Catch2-based C++ tests for the weak Node-API host injection functionality
• Updates code generation to use C++20 features and improve cross-platform compatibility
• Adds CI workflow for running C++ tests across multiple platforms

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
packages/weak-node-api/tests/test_inject.cpp	Adds two test cases verifying inject_weak_node_api_host functionality
packages/weak-node-api/tests/CMakeLists.txt	Configures Catch2 test executable with CTest integration
packages/weak-node-api/scripts/generate-weak-node-api.ts	Updates code generation for C++20 compatibility and adds unreachable macro
packages/weak-node-api/CMakeLists.txt	Upgrades to C++20 and adds optional test building
packages/weak-node-api/.gitignore	Adds clang cache directory to ignore list
.github/workflows/check.yml	Adds cross-platform CI job for running weak-node-api tests

[Copilot]

Corrected spelling of 'jod' to 'jodium'.

[Copilot]

The generated code will produce invalid C++ syntax. When noReturn is true, the unreachable macro appears after the semicolon and before the closing brace, creating ); WEAK_NODE_API_UNREACHABLE };. The macro should be placed before the semicolon or on its own line. Consider using ].filter(Boolean).join(" ") and including the semicolon with the return statement, or conditionally building the return line.