quantmodel — Align backtester with AS assumptions (same-close, 10bps, T-bill cash, month-end utils)

Objective

Align backtester with AS assumptions (same-close, 10bps, T-bill cash, month-end utils).

Notes: Engine AS alignment: same_close execution, BacktestConfig.allocatesmartly() 10bps, cash_daily_returns + download_tbill_daily_returns(^IRX), month_end/day_of_month helpers. Tests: 13 passed.

Approach

Reuses existing report research/findings/sqlite-datastore-t99.md — tables/metrics preserved verbatim via source_report pointer. Body below summarizes grounded evidence from that report and adjacent artifacts.

Files / code / data changed

No commit SHA confidently associated with t9 in sampled log [reconstructed — uncertain].
Source report: research/findings/sqlite-datastore-t99.md
Task-history entry: research/findings/task-history.json#t9

Results

Key table from source report (preserved):

Piece	Path
Module + CLI	`backtest/datastore.py` (`python3 -m backtest.datastore`)
Price wire-through	`backtest/data.py` → `download_ticker` / `download_history`
Macro wire-through	`backtest/macro.py` → `download_fred_series`
Tests	`tests/test_datastore.py` (8 cases; RO dirty-check)

Conclusions and metrics are in research/findings/sqlite-datastore-t99.md; see detail page for preserved tables/metrics.

Conclusions

[reconstructed — uncertain] Outcome inferred from status done and task note.

Problems / follow-ups

See source report or PR discussion for follow-ups. No unsupported follow-ups fabricated.