Consolidate prediction functionality by merging /api/prediction endpoint into /api/stations response. Move prediction logic from PredictionController into StationController, returning prediction data alongside station results. Replace usePrediction composable with unified useStations that returns {stations, meta, prediction}. Remove PredictionRequest, related tests, and unused Vue components (FuelFinderTest, MapTest, RecommendationTest, StationListTest). Add PredictionFull component and UpsellBanner. Extend NationalFuelPredictionService to include weekly_summary (7-day series, yesterday/today averages, cheapest/priciest days) and oil signal from price_predictions table. Update Home.vue to consume prediction from stations response. Add Plan::resolveCadenceForUser helper and configure Cashier to use custom Subscription model.
Implements PredictionRequest (fuel_type validation with ValueError→ValidationException), PredictionController delegating to NationalFuelPredictionService, and 5 feature tests. Also fixes LEAST() MySQL-only function to a CASE WHEN expression for SQLite test compatibility.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
