Sanitizer verification

FlowEdge provides a bounded Linux sanitizer lane for the Core loaders, protocol codecs, and Relay parser/process tests:

bash scripts/sanitize.sh

The script builds with Clang AddressSanitizer and UndefinedBehaviorSanitizer, then runs CTest with one test process at a time. Two build workers and one test worker are intentional peak-RSS limits for CI and small development machines. ASan reserves a large virtual shadow range, so the lane does not impose an address-space ulimit; doing so would prevent ASan from starting.

Set FLOWEDGE_SANITIZER_BUILD_DIR to keep the build outside the repository, or FLOWEDGE_SANITIZER_BUILD_JOBS to lower the build concurrency. On failure, Testing/Temporary/sanitizer-build.log and sanitizer-tests.log contain the compiler, failing test name, and sanitizer stack trace for CI artifact upload.