plan(lifecycle): bite-sized B0 plan — Dagster foundation + combined-book via warehouse
10 tasks: _panel extract, warehouse read_panel, CombinedBookSource port (Raw/Warehouse,
equivalence test = A->B guarantee), CombinedBook source-injection, config flag+factory,
dagster extra, 4 assets, Definitions+schedule, cluster deploy (webserver+daemon+pg+tailnet)
+ suspend the fxhnt-forward cron. Reversible cutover via FXHNT_COMBINED_BOOK_DATA_SOURCE.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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