feat(city): add plaza exercise system with health tracking

- Adds CityPlazas support class for deterministic public plaza generation with outdoor gym equipment
- Implements exercise and stop-exercise actions with proximity validation to equipment
- Introduces health (0-100) and exercise_count attributes to Character model
- Reduces hospital stay duration from two game days to one game hour
- Adds 3D gym equipment rendering (bench, bars, bike, treadmill) in city viewer
- Includes exercise state machine handling in world ticker with energy drain
- Adds comprehensive PlazaExerciseTest and updates HospitalAdmissionTest
- Provides localized UI strings for health HUD and exercise prompts

app/Console/Commands/CityTick.php

@@ -134,6 +134,13 @@ class CityTick extends Command
                 $character->energy = max(0, (int) $character->energy - (int) round(0.8 * $elapsedMin));
                 break;
 
+            case Character::STATE_EXERCISING:
+                $character->energy = max(0, (int) $character->energy - (int) round(1.0 * $elapsedMin));
+                if ((int) $character->energy <= 5) {
+                    $character->state = Character::STATE_AWAKE;
+                }
+                break;
+
             default:
                 $drain = $starving ? 0.8 : 0.4;
                 $character->energy = max(0, (int) $character->energy - (int) round($drain * $elapsedMin));
@@ -162,6 +169,13 @@ class CityTick extends Command
             return;
         }
 
+        // Offline exercise sessions end after the next tick so NPCs recover.
+        if ($character->state === Character::STATE_EXERCISING) {
+            $character->state = Character::STATE_AWAKE;
+
+            return;
+        }
+
         if ($character->energy < 20 && $character->house_id !== null) {
             $character->state = Character::STATE_SLEEPING;