Segmented control «Горизонт прогноза» driving the analyze query (?horizon=)
and Section 6's target highlight. Default 12.
- HorizonSelector: radiogroup + a11y radios, tokens-only, tabular-nums,
disabled while a re-analyze is in flight
- useParcelAnalyzeQuery(cad, horizon=12): horizon in queryKey + ?horizon=;
keepPreviousData so switching horizon doesn't blank the page to loading
- AnalysisPageContent: horizon state + forecast-poll invalidation on change
- Section6Forecast/ForecastHorizonsBlock: selectedHorizon → target row («Целевой»)
Part of EPIC #958.
