Phone users need the city card to answer what matters first instead of inheriting the full desktop analysis hierarchy. This adds a MobileDecisionCard that leads with city, observed temperature, expected high, peak window, one decision reason, status tags, freshness, and a separate market-price row, while keeping AI, model evidence, and the chart behind collapsible sections.
Constraint: Preserve the existing desktop city-card layout and decision state semantics.
Rejected: Continue relying only on CSS hide/show | it keeps mobile coupled to the desktop information architecture.
Confidence: high
Scope-risk: moderate
Reversibility: clean
Tested: TypeScript diagnostics for AiPinnedCityCard and MobileDecisionCard
Tested: npm run build
Not-tested: Device screenshot QA across iOS/Android viewport sizes.