fba2bbb17e
emitLlmArtifacts previously emitted ArtifactCreated/Validating/Validated for every llm-emitted slot unconditionally, fabricating "validated" artifacts when the model produced no content. Gate now mirrors the F-015 file_written check: slots with null or blank cached content are skipped with a warn log. Regression test added in NeedsArtifactInjectionTest verifies no artifact events appear for a blank-response stage.