Inventory: per-player items backbone (DR-026 Phase 0)

Data-driven ItemDatabase catalog + per-player replicated InventorySlot ([GhostField] OwnerSendType.All, a StatModifier twin). Harvest reroutes to the firing player's personal inventory (optional ComponentLookup<GhostOwner> in ResourceHarvestSystem; remainder/un-owned -> ledger); the G-key InventoryDepositRequest RPC moves the bag into the shared ledger the build economy spends. Catalog asset (Aether/Ore/Biomass + Stone Pickaxe) wired into the Gameplay subscene; read-only HUD inventory panel. ushort ItemId subsumes ResourceId; byte Category/Tier baked for gear-tier progression. Session-only (no SaveData bump).

Play-validated host+client: catalog baked into both worlds, the re-baked player ghost carries InventorySlot with a clean handshake, a server write replicates to the client owner, the deposit RPC round-trips, and the HUD renders catalog names. See DR-026.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Assets/_Project/Scripts/Simulation/Tuning.cs

@@ -56,5 +56,13 @@ namespace ProjectM.Simulation
         /// <summary>Max production cycles a single machine awards in one process (bounds within-session
         /// catch-up after any skipped ticks; restore re-seats the baseline so this never reflects wall-clock).</summary>
         public const int MaxProductionCatchup = 600;
+
+        // ---- Inventory (per-player bag; InventoryMath / ResourceHarvestSystem / InventoryDepositSystem) ----
+
+        /// <summary>Max stacks a player can carry; InventoryMath rejects deposits past this and the harvest remainder spills to the global ledger.</summary>
+        public const int InventoryMaxSlots = 24;
+
+        /// <summary>Default per-slot stack cap when an item has no ItemDatabase entry (the catalog is optional at runtime).</summary>
+        public const int DefaultStackMax = 999;
     }
 }