fix(rectification): use candidate dates for cross-midnight dasha scoring

Add date-isolated caches and regression coverage, align scoring identity, and freeze full research reruns while preserving historical artifacts. Record unresolved cache/receipt identity and end-to-end acceptance gaps for branch review only.

Co-Authored-By: Claude Code <noreply@anthropic.com>

tests/golden/rectification_engine_memoization_v1.json

@@ -42,7 +42,7 @@
     "confirmation_allowed": false,
     "accept_allowed": false,
     "confirm_allowed": false,
-    "representative_candidate_id": "85ca5490-07ab-54b7-acf0-59385f705015",
+    "representative_candidate_id": "e8c11277-022c-519c-95e9-6a0a04e8bf23",
     "representative_time": "12:00",
     "overall_confidence": "low",
     "margin_percent": 5.3006,
@@ -1150,7 +1150,7 @@
   },
   "candidate_feature_snapshot": {
     "calculation_spec_hash": "e03dfc555a247e78549768cc0b487cb427414633982212debd9cd6e60bb67292",
-    "algorithm_version": "rectification-v5-matrix-scoring-7",
+    "algorithm_version": "rectification-v5-matrix-scoring-8",
     "candidate_count": 3,
     "feature_hash": "36190982db75d3c9fe7c584607f25342531049c3d751060075519dbbd68033db",
     "features": [