refactor: simplify train debug logs to strings only

Changed from logging objects to simple string format:
- Before: { momentum: 50, trainPosition: 0, pressure: 60, ... }
- After: Sprint: momentum=50 pos=0 pressure=60

Issue identified from logs: trainPosition stuck at 0!
This is why train isn't appearing/moving.

apps/web/src/app/arcade/complement-race/components/RaceTrack/SteamTrainJourney.tsx

@@ -93,23 +93,8 @@ export function SteamTrainJourney({
   currentQuestion,
   currentInput,
 }: SteamTrainJourneyProps) {
-  console.log('🚂 [SteamTrainJourney] Render:', {
-    momentum,
-    trainPosition,
-    pressure,
-    elapsedTime,
-    currentQuestion,
-    currentInput,
-  })
-
   const { state } = useComplementRace()
-  console.log('🚂 [SteamTrainJourney] State from provider:', {
-    stations: state.stations,
-    passengers: state.passengers,
-    currentRoute: state.currentRoute,
-    gamePhase: state.gamePhase,
-    isGameActive: state.isGameActive,
-  })
+  console.log(`🚂 Train: mom=${momentum} pos=${trainPosition} stations=${state.stations.length} passengers=${state.passengers.length}`)
 
   const { getSkyGradient, getTimeOfDayPeriod } = useSteamJourney()
   const _skyGradient = getSkyGradient()

apps/web/src/arcade-games/complement-race/Provider.tsx

@@ -330,14 +330,7 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
     }
   }, [multiplayerState, localPlayerId, localUIState])
 
-  console.log('🚂 [Provider] Transformed sprint values:', {
-    momentum: compatibleState.momentum,
-    trainPosition: compatibleState.trainPosition,
-    pressure: compatibleState.pressure,
-    stations: compatibleState.stations?.length,
-    passengers: compatibleState.passengers?.length,
-    currentRoute: compatibleState.currentRoute,
-  })
+  console.log(`🚂 Sprint: momentum=${compatibleState.momentum} pos=${compatibleState.trainPosition} pressure=${compatibleState.pressure}`)
 
   // Action creators
   const startGame = useCallback(() => {