Period selection (date range, season, etc.) is now expressed as a
filter condition like any other — no separate date range section.
Preview uses a timeline/number-line bar instead of month chips.
Documents the unified filter builder approach.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Covers architecture, data model, API routes, SQL patterns, and UI design.
Includes baseline workbench design with multi-segment additive loads,
filter role for col_meta, and date offset for projecting actuals into
the forecast period.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>