This removes `fork-ts-checker-webpack-plugin` and instead directly calls the TypeScript API.
This is approximately 10x faster.
Base build: 7s (no TypeScript features enabled)
- `fork-ts-checker-webpack-plugin@3.1.1`: 90s, computer sounds like an airplane
- `fork-ts-checker-webpack-plugin@4.1.6`: 84s, computer did **not** sound like an airplane
- `fork-ts-checker-webpack-plugin@5.0.0-alpha.14`: 90s, regressed
- `npx tsc -p tsconfig.json --noEmit`: 12s (time: `18.57s user 0.97s system 169% cpu 11.525 total`)
- **This PR**: 22s, expected to get better when we run this as a side-car
All of these tests were run 3 times and repeat-accurate within +/- 0.5s.
92a12a2e20