Benchmark project builds and output sizes in CI
The benchmarks only replayed single bsc calls, so the build system's own work never showed. They now also build the base's tests/tests on one worker domain (clean, no-op, leaf edit, shared edit), adding the workers' allocations the build reports, and measure the .cmi/.cmti/.cmt/.cmj sizes and the playground bundle. Only the no-op and leaf-edit builds run under cachegrind: the larger ones take minutes, and with two domains collecting their instructions depend on how the domains interleave.
Review
- Why build the base's tests/tests on both sides? The base compiler builds them already, so a pull request adding tests with new syntax can't break the base measurement.