Keep transcript-only runs eligible for alignment heuristics instead of bailing out when the ASR stage does not supply word timings.
Build fallback AsrWord entries from the transcript so cue-based corrections like "i mean" still apply, while reusing the existing literal guard for verbatim phrases.
Cover the new path in alignment and pipeline tests, and validate with python3 -m unittest tests.test_alignment_edits tests.test_pipeline_engine.
