supply: buy whole numbers for each planet

this removes the math.ceil that was causing overcommit
andresolves ambiguity in how to split when 2 planets each want half a unit

supply.py

@@ -30,7 +30,7 @@ def main() -> None:
 		print(planet.name, f'consumes {vol_per_day:.1f}㎥, {weight_per_day:.1f}t per day')
 
 	load_more = True
-	optimal: dict[str, dict[str, float]] = dict.fromkeys(p.name for p in planets) # pyright: ignore[reportAssignmentType]
+	optimal: dict[str, dict[str, int]] = dict.fromkeys(p.name for p in planets) # pyright: ignore[reportAssignmentType]
 	target_days = round(target_days + 0.05, 1)
 	while load_more:
 		total_weight_used = total_volume_used = 0
@@ -57,8 +57,8 @@ def main() -> None:
 				print(f' | {need:8.1f}')
 			else:
 				print()
-	
-	combined_buy: dict[str, float] = collections.defaultdict(float)
+
+	combined_buy: dict[str, int] = collections.defaultdict(int)
 	for buy in optimal.values():
 		for ticker, amount in buy.items():
 			combined_buy[ticker] += amount
@@ -71,7 +71,7 @@ def main() -> None:
 		],
 		'global': {'name': 'supply ' + ' '.join(planet_names)},
 		'groups': [{
-			'type': 'Manual', 'name': 'A1', 'materials': {mat: math.ceil(amount) for mat, amount in combined_buy.items()}
+			'type': 'Manual', 'name': 'A1', 'materials': {mat: amount for mat, amount in combined_buy.items()}
 		}],
 	}))
 	for planet in planets:
@@ -83,7 +83,7 @@ def main() -> None:
 			],
 			'global': {'name': 'unload ' + planet.name},
 			'groups': [{
-				'type': 'Manual', 'name': 'A1', 'materials': {mat: round(amount) for mat, amount in buy.items()}
+				'type': 'Manual', 'name': 'A1', 'materials': {mat: amount for mat, amount in buy.items()}
 			}],
 		}))
 
@@ -135,16 +135,16 @@ class Planet:
 			c['net_consumption'] = net
 			self.net_consumption.append(c)
 
-	def buy_for_target(self, materials: dict[str, Material], target_days: float) -> tuple[dict[str, float], float, float]:
+	def buy_for_target(self, materials: dict[str, Material], target_days: float) -> tuple[dict[str, int], float, float]:
 		weight_used = volume_used = 0
-		buy: dict[str, float] = {}
+		buy: dict[str, int] = {}
 		for consumption in self.net_consumption:
 			ticker = consumption['MaterialTicker']
 			avail = self.inventory.get(ticker, 0)
 			daily_consumption = consumption['net_consumption']
 			days = avail / daily_consumption
 			if days < target_days:
-				buy[ticker] = (target_days - days) * daily_consumption
+				buy[ticker] = math.ceil((target_days - days) * daily_consumption)
 				weight_used += buy[ticker] * materials[ticker]['Weight']
 				volume_used += buy[ticker] * materials[ticker]['Volume']
 		return buy, weight_used, volume_used