queue: pre-registered experiment backlog to prove better-trading-performance hypotheses

Mined from book/ on the 'book' branch (HEAD 436692a). 11 queued runs,
each = hypothesis + one-variable change vs the exp-26 reference + acceptance
metric, per the ch.02 isolation/falsification discipline.

- workflows/: 5 runnable config-only YAMLs (Q01 M2 repro, Q02 seed10, Q03 topk20,
  Q04 label10d, Q05 label22d) byte-derived from the exp-26 reference
- designs/: 6 design docs needing custom strategy modules or tool-only A/B
  (Q06 Kelly, Q07 weekly rebalance, Q08 risk-limit A/B, Q09 long-short,
   Q10 HMM overlay, Q11 standalone reversal)

queue/designs/q09_long_short.md

@@ -0,0 +1,30 @@
+# QUEUE-09 — Long-short construction: capture the long-short edge net of costs
+
+**Status:** QUEUED · **Priority:** P2 · **Effort:** custom strategy module + run
+
+## Hypothesis (prove)
+The compact stochastic signal's long-short spread is the real edge (L/S ann
+Sharpe 4.54, exp 24; "edge is long-short, not long-only" — chat-ideas.md), but
+all canonical constructions are long-only (TopkDropout buys topk, drops, holds).
+A market-neutral book (long topk, short bottom topk) should realize more of the
+spread net of costs than the long-only book, IF short-side financing + doubled
+turnover cost stays below the added spread capture.
+
+## Change vs exp-26 reference (ONE variable)
+- **Strategy**: long-only TopkDropout (topk 10, n_drop 1) → custom
+  `TopBottomDropoutStrategy` (long topk by rank, short bottom topk, equal
+  weight per side, same risk_degree), realized in a workflow with a cost model
+  that includes both sides (open/close cost symmetric).
+- All signal/config unchanged.
+
+## Acceptance
+- `net_IR > 0.21` AND `net_ann_return > +2.13%` AND `total_cost` within ~2× the
+  reference (doubled side count is the structural cost of this construction).
+- Watch: benchmark neutrality (SPY beta ≈ 0) as a secondary sanity metric.
+
+## Execution prerequisites
+1. New contrib module `tac_qlib/contrib/strategy/top_bottom.py`
+   (`TopBottomDropoutStrategy` subclassing `BaseSignalStrategy`), copy to the
+   venv site-packages copy.
+2. Workflow YAML wiring the strategy; PortAnaRecord benchmark SPY.
+3. Trace + run + snapshot.