Don't error on referenced project's noEmit if program has empty files

[gabritto]

Fixes what seems like a porting bug in checking config references. If a tsconfig has no files (i.e. it's a top-level tsconfig that refers every project entry point in your monorepo), it's ok for a project it references to have noEmit true (same for having composite false).

[Copilot]

Pull Request Overview

This PR fixes a bug in the validation of TypeScript project references where the compiler incorrectly errored on referenced projects with noEmit: true or composite: false when the parent project had no files. The fix ensures that these validation errors only occur when the parent project actually contains files to compile.

• Changes the condition to check the parent project's files instead of the referenced project's files
• Adds a test case demonstrating a valid scenario where a parent config with empty files references a project with noEmit: true

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
internal/compiler/program.go	Fixes the validation logic to check parent project files instead of referenced project files
internal/execute/tsc_test.go	Adds test case for valid config reference scenario with empty parent files

[jakebailey]

The old code said:

const inputs = parent ? parent.commandLine.fileNames : rootNames;
if (inputs.length) {

I assume parent simply always exists?

[gabritto]

Seems to be the case in Corsa: this function starts with ref := parent.ProjectReferences()[index], which would crash if parent is nil.

[sheetalkamat]

thanks. yes with being able to use and store parsedCommandLine in program, we always have parent
I had this in #1484 fixed incorrectly too (was always checking program's file names) so thank you for doing the right fix.