chore(release): 0.9.0

[eaitbrahim]

What & why

Version bump across all six distributions; closes #339's first checkbox. Minor (0.9.0), not patch: the changes since v0.8.1 are a feature set —

• feat(backtest): per-product slippage scaled from liquidity — assumed, capped, and reported (#259) #334 per-product backtest slippage scaled from liquidity (5–50bp, assumed/capped/reported) — the honest cost model;
• fix(executor): warn loudly when a conditional entry price is overridden by market routing (#260) #332 the executor's routing-time WARNING when a conditional entry is overridden (The live executor discards a rule's conditional entry price and routes a market order regardless #260's mitigation);
• chore(fidelity): close Phase 9's loose ends — alias, stale docstrings, telemetry overflow guard #336 the Phase 9 cleanup (floor alias, stale docstrings, telemetry overflow guard);
• Pool min_trades across same-parameter rules, with a cross-sectional diversity floor #338 pooled min_trades with a cross-sectional diversity floor — the promotion gate can now count evidence collected across the universe;
• An hourly-cadence paper profile — evidence at a collectable rate #337 the hourly-cadence paper profile (turtle's granularity became a persisted param, daily default unchanged) — evidence at a collectable rate;
• Rail-17 withdrawal attestation cadence — the 7-day TTL needs a visible refresh habit #340 rail-17 attestation expiry visible in keel status/TUI before it vetoes, and the keel rules enable verb.

No rail, rule, or default classification changed semantics; the promotion gate changed its unit of evaluation per the operator-approved #338, floors untouched.

Tests-first evidence

tests/test_packaging.py pins the sibling-== invariants; after the bump and uv lock: 2947 passed, 1 skipped; ruff clean; mypy clean.

Gates

• uv run ruff check keel tests packages — All checks passed!
• uv run mypy — Success: no issues found in 238 source files
• uv run pytest -q — 2947 passed, 1 skipped

Scope check

• Version numbers and uv.lock only.