Add ASAN to root CMake

[nicholasbl]

AddressSanitizer is a great feature that helps catch memory safety issues early (heap/stack buffer overflows, use-after-free, etc.), and makes debugging crashes far easier during development.

This PR adds an opt-in AddressSanitizer build configuration controlled by a new CMake option:

• SOLTRACE_ENABLE_ASAN (by default, this is OFF)

When enabled and the project is built with Clang or GCC, the build will compile and link with -fsanitize=address. Note that this is not supported on MSVC; in this case, CMake will skip the flags. This is added to the root CMake so that all code (including third-party) can be covered. ASan is not added to the CI matrix in this PR, but can be, later on.

To enable ASan at configure time:

cmake -S . -B build-asan -DSOLTRACE_ENABLE_ASAN=ON -DCMAKE_BUILD_TYPE=Debug
cmake --build build-asan
ctest --test-dir build-asan

Note that this will inflate execution time as it adds additional instrumentation to the code.

[Copilot]

Pull request overview

Adds an opt-in AddressSanitizer (ASan) configuration at the root CMake level so the entire build (including third-party) can be instrumented when using supported compilers.

Changes:

• Introduces SOLTRACE_ENABLE_ASAN CMake option (default OFF).
• When enabled, applies -fsanitize=address (and -fno-omit-frame-pointer) for supported compilers, with warnings for unsupported toolchains (e.g., MSVC).

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[Copilot]

CMAKE_CXX_COMPILER_ID MATCHES "Clang|GNU" excludes AppleClang, so ASan won't be enabled on macOS even though AppleClang supports -fsanitize=address. Consider including AppleClang in the check (or using a more robust compiler-ID test) to match the PR description (“Clang or GCC”).

[jmaack24]

Would there be any objections to adding AppleClang to the compiler check? I tried this on my Mac and had issues using this with the GCC compiler, but AppleClang worked just fine.

[nicholasbl]

Sure. It's probably a solid idea to just restrict this to Clang + AppleClang at the moment as Clang does a much better job at keeping the runtimes OK with ASAN active. Let me update the branch...