feat: image version identity + DB-config parity for nightly scripts

Version: CI now tags images YYYY.MM.DD-<shortsha> alongside :latest/:sha
and passes GIT_SHA/BUILD_TAG build-args; the running app reports them via
dashboard /api/health and admin /api/status (TrueNAS custom apps only show
'custom/1.0.0', so the app self-reports what it actually runs).

Config parity: every scheduler-run script (nightly_tune, eod_replay,
premarket_eval, regime, market_context, experiments cli) now loads
config_overrides at startup like the live services do — a bare env would
replay under DEFAULT exits (the documented 4.5x-baseline landmine).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

research/ingestion/market_context.py

@@ -26,6 +26,12 @@ from research.ingestion.market_data import (  # noqa: E402
     upsert_daily_bars, upsert_minute_bars)
 from research.multi_schema import open_research_db  # noqa: E402
 
+# config parity with the live loop: DB-backed knobs (config_overrides) beat
+# compose env — a bare env would replay under DEFAULT exits (the 4.5x-baseline
+# landmine, orderflow-shelf-verdicts 2026-07-17)
+from runtime.env_overrides import load as _load_cfg_overrides  # noqa: E402
+_load_cfg_overrides()
+
 INDEX_SYMBOLS = ("SPY", "QQQ")