Add MVP inventory HUD panel

AGRARIAN_DEVELOPMENT_ROADMAP.md

@@ -515,7 +515,9 @@ Target deliverable: A small group can join a server, spawn into one biome, gathe
   thresholds, strength-scaled movement penalties, and a debug HUD carried
   weight readout. Later volume, backpack, awkward-object, and hard overload
   rules should extend this hook.
-- [ ] Add inventory UI.
+- [x] Add inventory UI. Added a compact MVP HUD inventory panel that is separate
+  from the full developer HUD and shows occupied slots, total carried weight,
+  and visible item stacks from the replicated inventory component.
 - [x] Add replication for inventory changes.
 - [ ] Add persistence for inventory.
 - [x] Add debug item spawn command.

Docs/InventoryDataModel.md

@@ -119,6 +119,8 @@ The 0.1.E inventory work should implement these operations on top of the model:
 - Carry capacity: continue using total weight first, with later volume or pack
   systems layered on top.
 - UI: read the replicated stack list and send requests back through server RPCs.
+  The MVP HUD now includes a compact inventory panel that shows occupied slots,
+  total carried weight, and the first visible item stacks.
 
 ## Carry Capacity Placeholder
 

Docs/TechnicalDesignDocument.md

@@ -138,6 +138,12 @@ HUD. Future backpacks, containers, awkward-object rules, and hard overload
 limits should extend this total-weight path rather than creating a second carry
 model.
 
+The MVP inventory UI is a compact `AAgrarianDebugHUD` inventory panel, enabled
+separately from the full developer HUD. It reads the replicated inventory stack
+array, shows occupied slots, total carried weight, and a short visible stack
+list, and leaves mutation actions on the existing server-authoritative commands
+and RPCs until a full UMG inventory screen is introduced.
+
 ## Time And Environment
 
 The MVP gameplay calendar target is:

Scripts/verify_inventory_ui.py

@@ -0,0 +1,66 @@
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[1]
+FILES = {
+    "AgrarianDebugHUD.h": ROOT / "Source" / "AgrarianGame" / "AgrarianDebugHUD.h",
+    "AgrarianDebugHUD.cpp": ROOT / "Source" / "AgrarianGame" / "AgrarianDebugHUD.cpp",
+    "InventoryDataModel.md": ROOT / "Docs" / "InventoryDataModel.md",
+    "TechnicalDesignDocument.md": ROOT / "Docs" / "TechnicalDesignDocument.md",
+    "AGRARIAN_DEVELOPMENT_ROADMAP.md": ROOT / "AGRARIAN_DEVELOPMENT_ROADMAP.md",
+}
+
+EXPECTED = {
+    "AgrarianDebugHUD.h": [
+        "bShowInventoryHUD",
+        "InventoryTextScale",
+        "MaxInventoryPanelRows",
+        "DrawInventoryPanel",
+    ],
+    "AgrarianDebugHUD.cpp": [
+        "DrawInventoryPanel(AgrarianCharacter)",
+        "AAgrarianDebugHUD::DrawInventoryPanel",
+        "InventoryComponent->Items.Num()",
+        "InventoryComponent->MaxSlots",
+        "InventoryComponent->GetTotalWeight()",
+        "MaxInventoryPanelRows",
+        "Stack.UnitWeight * Stack.Quantity",
+    ],
+    "InventoryDataModel.md": [
+        "compact inventory panel",
+        "occupied slots",
+        "total carried weight",
+        "visible item stacks",
+    ],
+    "TechnicalDesignDocument.md": [
+        "The MVP inventory UI is a compact `AAgrarianDebugHUD` inventory panel",
+        "enabled",
+        "separately from the full developer HUD",
+        "shows occupied slots",
+        "total carried weight",
+        "server-authoritative commands",
+    ],
+    "AGRARIAN_DEVELOPMENT_ROADMAP.md": [
+        "[x] Add inventory UI.",
+        "compact MVP HUD inventory panel",
+        "replicated inventory component",
+    ],
+}
+
+
+def main():
+    missing = []
+    for label, path in FILES.items():
+        text = path.read_text(encoding="utf-8")
+        for snippet in EXPECTED[label]:
+            if snippet not in text:
+                missing.append(f"{label}: {snippet}")
+
+    if missing:
+        raise RuntimeError("Inventory UI verification failed: " + "; ".join(missing))
+
+    print("Agrarian inventory UI verification complete.")
+
+
+if __name__ == "__main__":
+    main()

Source/AgrarianGame/AgrarianDebugHUD.cpp

@@ -24,6 +24,7 @@ void AAgrarianDebugHUD::DrawHUD()
 
 	DrawInteractionPrompt(AgrarianCharacter);
 	DrawCriticalStats(AgrarianCharacter->GetSurvivalComponent());
+	DrawInventoryPanel(AgrarianCharacter);
 
 	if (bShowDebugHUD)
 	{
@@ -109,6 +110,73 @@ void AAgrarianDebugHUD::DrawCriticalStats(const UAgrarianSurvivalComponent* Surv
 	DrawScaledLine(FString::Printf(TEXT("Sickness  %3.0f"), Survival.SicknessSeverity), X, Y, CriticalStatsTextScale, StatusColor(Survival.SicknessSeverity, true));
 }
 
+void AAgrarianDebugHUD::DrawInventoryPanel(const AAgrarianGameCharacter* AgrarianCharacter)
+{
+	if (!bShowInventoryHUD || !AgrarianCharacter || !Canvas)
+	{
+		return;
+	}
+
+	const UAgrarianInventoryComponent* InventoryComponent = AgrarianCharacter->GetInventoryComponent();
+	if (!InventoryComponent)
+	{
+		return;
+	}
+
+	const float Scale = FMath::Max(0.25f, InventoryTextScale);
+	const float PanelWidth = 360.0f * Scale;
+	const float X = FMath::Max(32.0f, Canvas->ClipX - PanelWidth - 32.0f);
+	float Y = 32.0f;
+
+	const int32 VisibleRows = InventoryComponent->Items.IsEmpty()
+		? 1
+		: FMath::Min(InventoryComponent->Items.Num(), FMath::Max(1, MaxInventoryPanelRows));
+	const float LineHeight = 18.0f * Scale;
+	const float PanelHeight = (56.0f * Scale) + (VisibleRows * LineHeight);
+
+	DrawRect(FLinearColor(0.02f, 0.025f, 0.02f, 0.72f), X - (12.0f * Scale), Y - (10.0f * Scale), PanelWidth, PanelHeight);
+	DrawText(
+		FString::Printf(
+			TEXT("INVENTORY  %d/%d slots  %.1f wt"),
+			InventoryComponent->Items.Num(),
+			InventoryComponent->MaxSlots,
+			InventoryComponent->GetTotalWeight()),
+		FColor(160, 220, 140),
+		X,
+		Y,
+		nullptr,
+		Scale,
+		false);
+	Y += 24.0f * Scale;
+
+	if (InventoryComponent->Items.IsEmpty())
+	{
+		DrawText(TEXT("Empty"), FColor::Silver, X, Y, nullptr, Scale, false);
+		return;
+	}
+
+	for (int32 Index = 0; Index < VisibleRows; ++Index)
+	{
+		const FAgrarianItemStack& Stack = InventoryComponent->Items[Index];
+		const FText DisplayName = Stack.DisplayName.IsEmpty() ? FText::FromName(Stack.ItemId) : Stack.DisplayName;
+		FString ItemName = DisplayName.ToString();
+		if (ItemName.Len() > 24)
+		{
+			ItemName = ItemName.Left(21) + TEXT("...");
+		}
+
+		DrawText(
+			FString::Printf(TEXT("%02d  %-24s x%-3d %5.1f"), Index + 1, *ItemName, Stack.Quantity, Stack.UnitWeight * Stack.Quantity),
+			FColor(225, 235, 220),
+			X,
+			Y,
+			nullptr,
+			Scale,
+			false);
+		Y += LineHeight;
+	}
+}
+
 void AAgrarianDebugHUD::DrawPlayerStatus(const AAgrarianGameCharacter* AgrarianCharacter, float X, float& Y)
 {
 	if (!AgrarianCharacter)

Source/AgrarianGame/AgrarianDebugHUD.h

@@ -23,12 +23,21 @@ public:
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|HUD")
 	bool bShowCriticalStatsHUD = true;
 
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|HUD")
+	bool bShowInventoryHUD = true;
+
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|HUD", meta = (ClampMin = "0.25"))
 	float TextScale = 1.0f;
 
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|HUD", meta = (ClampMin = "0.25"))
 	float CriticalStatsTextScale = 1.0f;
 
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|HUD", meta = (ClampMin = "0.25"))
+	float InventoryTextScale = 0.9f;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|HUD", meta = (ClampMin = "1", ClampMax = "12"))
+	int32 MaxInventoryPanelRows = 6;
+
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|HUD")
 	bool bShowInteractionPrompt = true;
 
@@ -38,6 +47,7 @@ public:
 protected:
 	void DrawInteractionPrompt(const class AAgrarianGameCharacter* AgrarianCharacter);
 	void DrawCriticalStats(const UAgrarianSurvivalComponent* SurvivalComponent);
+	void DrawInventoryPanel(const class AAgrarianGameCharacter* AgrarianCharacter);
 	void DrawPlayerStatus(const class AAgrarianGameCharacter* AgrarianCharacter, float X, float& Y);
 	void DrawSurvival(const UAgrarianSurvivalComponent* SurvivalComponent, float X, float& Y);
 	void DrawInventory(const UAgrarianInventoryComponent* InventoryComponent, float X, float& Y);