Support non-standard compilation processes

In a recent talk with @adityasharad , he mentioned that CodeQL would try to understand when a compiler is being invoked. Some projects use [goma](https://chromium.googlesource.com/infra/goma/server/+/refs/tags/v0.0.1/README.md) to speed up the build process, reusing previously built artifacts.

CodeQL seems to ignore all the artifacts that are obtained via goma.

Start by reading the linked goma README and tracing how CodeQL identifies compiler invocations and handles artifacts obtained through goma. No source files or tests are named; done means defining and validating support for those artifacts so CodeQL no longer ignores them.

Written by the indexing model from the issue text.