Fix compute utilization bug and add subscriber saturation cap

Three intertwined fixes:

1. Zero-capacity utilization: when inference allocation was 0%, the
   guard clause returned 0% utilization instead of 100%, so the market
   system never penalized satisfaction and subscribers never churned.

2. Stale compute in market: restructured tick order so capacity is
   computed before market runs, giving satisfaction calculations
   current-tick demand/capacity ratio instead of previous tick's.

3. Subscriber growth: replaced pure compound growth (reached billions
   in minutes) with logistic saturation curve. Era-based market caps:
   startup 10K, scaleup 1M, bigtech 20M, agi 100M. Quality and
   reputation expand the effective cap.

Also tuned FLOPS-to-tokens multiplier (10 → 26) for balanced
demand/capacity feel across all eras, and added market saturation
indicator to the Market page.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/game-engine/src/tick.ts

@@ -1,7 +1,7 @@
 import type { GameState, AchievementDefinition } from '@ai-tycoon/shared';
 import { processEconomy } from './systems/economySystem';
 import { processInfrastructure } from './systems/infrastructureSystem';
-import { processCompute } from './systems/computeSystem';
+import { computeCapacity, finalizeCompute } from './systems/computeSystem';
 import { processResearch } from './systems/researchSystem';
 import { processModels } from './systems/modelSystem';
 import { processMarket } from './systems/marketSystem';
@@ -49,13 +49,10 @@ export function processTick(state: GameState): Partial<GameState> {
   }
 
   const stateWithModels = { ...stateWithInfra, models: modelResult.modelsState };
-  const market = processMarket(stateWithModels, state.compute);
 
-  const compute = processCompute(state, infrastructure);
-  compute.tokensPerSecondDemand = market.totalTokenDemand;
-  compute.inferenceUtilization = compute.tokensPerSecondCapacity > 0
-    ? Math.min(1, market.totalTokenDemand / compute.tokensPerSecondCapacity)
-    : 0;
+  const capacity = computeCapacity(state, infrastructure);
+  const market = processMarket(stateWithModels, capacity.tokensPerSecondCapacity);
+  const compute = finalizeCompute(capacity, market.totalTokenDemand);
 
   const talent = processTalent(stateWithModels);
   const stateWithTalent = { ...stateWithModels, talent };