Fix empty files diagnostics reporting

[csantos42]

Fixes #26779
Fixes #26780

This PR aligns the diagnostic reporting for empty files with the behavior described in the handbook:

Note that starting with 3.0, it is no longer an error to have an empty files array if you have at least one reference in a tsconfig.json file.

Specifically, the following 3 issues are addressed by this PR:

• The command-line parser logs errors whenever files is empty, regardless of the value of references
• The configFileParsingDiagnostics are not being passed to createProgram from buildSingleProject, meaning any parsing errors will go unreported
• For the queue of projects being processed in buildAllProjects, errors will go unreported if the for-loop iteration is continued because the errors are reported in buildSingleProject, which is at the end of the loop iteration

Unit tests are included to account for the new behavior.

[csantos42]

Thanks for the review @sheetalkamat — are we ready to merge?