Add Tier 1 review automation to catch issues before human review:
- Add cppcheck and clang-format to CI lint job
- Add sanitizer matrix (ASan + TSan) CI job
- Enable -Wextra -Wpedantic -Werror in CI build
- Add SANITIZER and STRICT_WARNINGS CMake options
- Add .clang-format for consistent code style
- Update Dockerfile with cppcheck and clang-format
- Fix sign-compare and unused-parameter warnings for -Werror
