Warenwirtschaft: OPT-3 Index-Limits + OPT-4 show()-Refactoring

- Wareneingang-/Produktions-Uebersicht: Eingegangene auf 500 gedeckelt
  (offene Bestellungen immer vollstaendig), ?all=1 + Hinweis-Link;
  ungenutzte User-Eager-Loads entfernt
- RawMaterialStockController::show() entschlackt: Chargen-Restmengen (FEFO)
  und offene Bestellungen im InventoryService, letzter Netto-Preis je
  Lieferant als Window-Function-Query im StockEntryRepository

Tests: RawMaterialStockTest +2, volle Suite 186 gruen, 663 Assertions

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app/Repositories/StockEntryRepository.php

@@ -120,12 +120,35 @@ class StockEntryRepository
             ->get();
     }
 
+    /**
+     * Letzter Netto-kg-Preis je Lieferant für einen Rohstoff (neuester Einkauf zählt).
+     *
+     * @return array<int, float> [supplier_id => price_per_kg_net]
+     */
+    public function lastNetPricePerSupplier(int $ingredientId): array
+    {
+        $ranked = StockEntry::query()
+            ->selectRaw('supplier_id, price_per_kg, ROW_NUMBER() OVER (PARTITION BY supplier_id ORDER BY ordered_at DESC, id DESC) as rn')
+            ->where('entry_type', 'ingredient')
+            ->where('ingredient_id', $ingredientId)
+            ->whereNotNull('supplier_id')
+            ->whereNotNull('price_per_kg');
+
+        return StockEntry::query()
+            ->fromSub($ranked, 'ranked')
+            ->where('rn', 1)
+            ->pluck('price_per_kg', 'supplier_id')
+            ->map(fn ($price) => (float) $price)
+            ->all();
+    }
+
     /**
      * Liste: Pending zuerst (neuestes Bestelldatum), dann Received (neuester Eingang).
+     * Eingegangene Einträge sind auf $receivedLimit gedeckelt (OPT-3); null = alle.
      *
      * @return Collection<int, StockEntry>
      */
-    public function listForIndex(): Collection
+    public function listForIndex(?int $receivedLimit = 500): Collection
     {
         $with = [
             'ingredient',
@@ -133,12 +156,20 @@ class StockEntryRepository
             'supplier',
             'location',
             'quality',
-            'orderedByUser',
-            'receivedByUser',
         ];
 
-        $pending = StockEntry::query()->with($with)->where('status', 'pending')->orderByDesc('ordered_at')->get();
-        $received = StockEntry::query()->with($with)->where('status', 'received')->orderByDesc('received_at')->get();
+        $pending = StockEntry::query()->with($with)
+            ->where('status', 'pending')
+            ->orderByDesc('ordered_at')
+            ->orderByDesc('id')
+            ->get();
+
+        $received = StockEntry::query()->with($with)
+            ->where('status', 'received')
+            ->orderByDesc('received_at')
+            ->orderByDesc('id')
+            ->when($receivedLimit !== null, fn ($q) => $q->limit($receivedLimit))
+            ->get();
 
         return $pending->concat($received)->values();
     }