OptionalredirectedReference: ResolvedProjectReferenceOptionalredirectedReference: ResolvedProjectReferenceUpdates with the current compilerOptions the cache will operate with. This updates the redirects map as well if needed so module resolutions are cached if they can across the projects
Stored map from non-relative module name to a table: directory -> result of module lookup in this directory We support only non-relative module names because resolution of relative module names is usually more deterministic and thus less expensive.