feat: starvation balance rework and Ghibli wind-stroke visuals

- Reduce hunger rate to 0.125/tick (~25/day) for ~6-7 day death timeline
- Slow energy drain: idle 0.125, travel 0.5, work 0.5, complete 0.0625/tick
- Use exact binary fractions for all rates to preserve float precision in save/load
- Starving/critically-hungry NPCs always override sleep to seek food first
- Extend starvation death threshold from 20 to 600 ticks (~3 days of starvation)
- Add calligraphy-style wind stroke particles (WindStrokes scene + shader)
- Two wind stroke emitters in valley and ridge for Ghibli atmosphere
- Rework terrain macro-variation colors for vibrant warm-green palette
- Enhance environment: stronger glow/bloom, higher saturation, warmer sky/fog/ambient

simulation/actions/ActionSelectionSystem.gd

@@ -22,6 +22,31 @@ func select_action(npc: SimNPC, village: SimVillage, time_of_day: float = 0.5) -
 	if npc.is_dead:
 		return null
 
+	if npc.is_starving:
+		if npc.get_inventory_amount(SimulationIds.RESOURCE_FOOD) >= 1.0:
+			return ActionSelectionResult.new(
+				SimulationIds.ACTION_EAT, 1.0, "Starving and carrying food"
+			)
+		if village.food > 0:
+			return ActionSelectionResult.new(
+				SimulationIds.ACTION_WITHDRAW_FOOD, 1.0, "Starving; pantry has food"
+			)
+		return ActionSelectionResult.new(
+			SimulationIds.ACTION_GATHER_FOOD, -1.0, "Starving; must find food"
+		)
+	if npc.hunger > 80.0:
+		if npc.get_inventory_amount(SimulationIds.RESOURCE_FOOD) >= 1.0:
+			return ActionSelectionResult.new(
+				SimulationIds.ACTION_EAT, -1.0, "Critically hungry and carrying food"
+			)
+		if village.food > 0:
+			return ActionSelectionResult.new(
+				SimulationIds.ACTION_WITHDRAW_FOOD, -1.0, "Critically hungry; pantry has food"
+			)
+		return ActionSelectionResult.new(
+			SimulationIds.ACTION_GATHER_FOOD, -1.0, "Critically hungry; must find food"
+		)
+
 	var period := _get_period(time_of_day)
 
 	if period == SchedulePeriod.SLEEP: