research: archive Task 1 sector residual as CLOSED/REJECTED

Deep masked retest failed the iron IC bar (0.027 < 0.03). Log as rejected #13 in
research README; close sector-residual and history-depth docs. Production market
residual unchanged.

docs/research/README.md

@@ -47,6 +47,7 @@ score, Structural S/R, the Gate Target Ladder, sentiment, fundamentals) is
 | 10 | **Inverse-vol position sizing** | The apparent "win" was **mis-attributed**: the 20% notional cap bound on 95% of entries, so it measured concentration, not vol-sizing. Genuine inverse-vol cuts DD to −18.2% but costs ~58pp return at flat Sharpe | **Rejected** as edge; it's a risk-preference trade | `backtest-20260709-position-sizing*.json` |
 | 11 | **FIP path-smoothness** as tie-breaker/filter | Non-monotonic within the qualified set; thinning the entry stream costs more compounding than the tilt returns | **Rejected as a filter** — but see §4, it's the strongest raw signal we've measured | — |
 | 12 | **Fixed take-profit sweep** (R-multiples) | No interior optimum ever found — the best TP is "no TP" | **Rejected.** Momentum's edge lives in the right tail | `backtest_service.py:450` |
+| 13 | **Sector-residual 12-1** (`mom_12_1_sector_resid` / sector demean) as replacement for market residual | Short-window IC/A/B looked knife-edge green; deep repaired + **liquid-1500** retest: weeks 83, mild +IC **0.027** / t 1.69, **below iron bar 0.03** (FAIL). Demean already weaker | **Rejected / closed.** Keep production market residual. Do not resurrect without a new pre-registered protocol | [sector-residual-momentum.md](sector-residual-momentum.md) · `sector-resid-deep-20260719-113319.json` · history-depth supersession note |
 
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