Add benchmark-driven model promotion workflow and pipeline stages

tests/test_alignment_edits.py

@@ -0,0 +1,72 @@
+import sys
+import unittest
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+SRC = ROOT / "src"
+if str(SRC) not in sys.path:
+    sys.path.insert(0, str(SRC))
+
+from stages.alignment_edits import AlignmentHeuristicEngine
+from stages.asr_whisper import AsrWord
+
+
+def _words(tokens: list[str], step: float = 0.2) -> list[AsrWord]:
+    out: list[AsrWord] = []
+    start = 0.0
+    for token in tokens:
+        out.append(
+            AsrWord(
+                text=token,
+                start_s=start,
+                end_s=start + 0.1,
+                prob=0.9,
+            )
+        )
+        start += step
+    return out
+
+
+class AlignmentHeuristicEngineTests(unittest.TestCase):
+    def test_returns_original_when_no_words_available(self):
+        engine = AlignmentHeuristicEngine()
+
+        result = engine.apply("hello world", [])
+
+        self.assertEqual(result.draft_text, "hello world")
+        self.assertEqual(result.applied_count, 0)
+        self.assertEqual(result.decisions, [])
+
+    def test_applies_i_mean_tail_correction(self):
+        engine = AlignmentHeuristicEngine()
+        words = _words(["set", "alarm", "for", "6", "i", "mean", "7"])
+
+        result = engine.apply("set alarm for 6 i mean 7", words)
+
+        self.assertEqual(result.draft_text, "set alarm for 7")
+        self.assertEqual(result.applied_count, 1)
+        self.assertTrue(any(item.rule_id == "cue_correction" for item in result.decisions))
+
+    def test_preserves_literal_i_mean_context(self):
+        engine = AlignmentHeuristicEngine()
+        words = _words(["write", "exactly", "i", "mean", "this", "sincerely"])
+
+        result = engine.apply("write exactly i mean this sincerely", words)
+
+        self.assertEqual(result.draft_text, "write exactly i mean this sincerely")
+        self.assertEqual(result.applied_count, 0)
+        self.assertGreaterEqual(result.skipped_count, 1)
+
+    def test_collapses_exact_restart_repetition(self):
+        engine = AlignmentHeuristicEngine()
+        words = _words(["please", "send", "it", "please", "send", "it"])
+
+        result = engine.apply("please send it please send it", words)
+
+        self.assertEqual(result.draft_text, "please send it")
+        self.assertEqual(result.applied_count, 1)
+        self.assertTrue(any(item.rule_id == "restart_repeat" for item in result.decisions))
+
+
+if __name__ == "__main__":
+    unittest.main()