perf(build): measure building without exceptions #32

Goal

Decide with numbers whether the engine builds without exceptions (-fno-exceptions with Clang, /EHs-c- and _HAS_EXCEPTIONS=0 with clang-cl).

Scope

• A test campaign comparing the same release build with and without exceptions, on Linux and Windows: binary size, build time, and run time on benchmarks of the hot paths (logging, Result propagation, then rendering once it exists).
• Check what breaks without exceptions: the standard library calls abort() where it would throw, vcpkg dependencies (doctest needs DOCTEST_CONFIG_NO_EXCEPTIONS, which drops CHECK_THROWS).
• A short report in the PR with the numbers and a recommendation; turning exceptions off, if recommended, is a separate change.

How to verify

• The report gives size, build time and benchmark times for both builds, with the commands to reproduce them.

Dependencies

Benchmarks of representative hot paths (after M0).

Suggested model

sonnet