Add headline sentence (N строящихся · велосити · mix%) and a 3-card KPI
row (Активные / Велосити / Срок продаж) before any other content in
MarketTab, so the financial director sees the verdict above the fold
without scrolling.
- Headline uses var(--bg-headline) dark bar per UI_Brief_GenDesign_May17
- KPI cards: grid-cols-3, bg-white border border-slate-200 rounded-lg p-3
- Derives radius_km from market_trend.radius_km or pipeline_24mo.radius_km
- Derives velocity from data.velocity.monthly_velocity_sqm (existing field)
- Derives maxMixPct from success_recommendation.ranking max success_score
- Derives salesPeriodMonths from pipeline_24mo.flats_total / velocity
- site_status filter deferred to fix #2/#3 (field not yet in type)
