feat(ECR-007): Wyckoff Live Structure with Confirmed/Live isolation

Add live.py lifecycle and event candidates; assemble confirmed vs live
in engine; Summary partition; execution_signal source=confirmed only.
Keep strategies untouched; do not lower Confirmed thresholds for Live.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/HANDOFF/ECR-007-code-review.md

@@ -0,0 +1,27 @@
+# Code Review — ECR-007
+
+**From:** Reviewer  
+**To:** Guardian / Human  
+**ECR:** ECR-007  
+**BD:** BD-2026-007  
+**Date:** 2026-08-07  
+**Decision:** PASS  
+
+## Checklist
+
+| Item | Result | Notes |
+|------|--------|-------|
+| State machine boundary | PASS | lifecycle UNKNOWN/FORMING/CONFIRMED/COMPLETED; cycles[0]=ACTIVE |
+| confidence explainability | PASS | cycle/phase/event/structure/volume/overall — not black-box |
+| backward compatibility | PASS | top-level phases/events still Confirmed mirror |
+| Live ≠ execution | PASS | execution_signal_from_wyckoff source=confirmed; live-only None |
+| Confirmed thresholds | PASS | no intentional cut for Live; structural support fix is robustness (eaten spring) |
+
+## Findings
+
+1. Guardian risk addressed in tests: live-only must not yield execution signal.  
+2. Summary UI partitions Confirmed vs Live (observation).  
+
+## Decision
+
+**PASS**