Save MVP player identity metadata

AGRARIAN_DEVELOPMENT_ROADMAP.md

@@ -733,7 +733,10 @@ Target deliverable: A small group can join a server, spawn into one biome, gathe
 
 - [x] Decide MVP persistence scope.
 - [x] Decide what tile metadata is stored in save data vs external tile registry.
-- [ ] Save player identity.
+- [x] Save player identity. Player save records now keep a
+  backwards-compatible `PlayerId` plus `FAgrarianSavedPlayerIdentity`, prefer a
+  valid `APlayerState` network ID when available, and retain safe display/pawn
+  metadata without storing credentials.
 - [ ] Save player stats.
 - [ ] Save long-term character care history placeholders without applying aging gameplay yet.
 - [ ] Save player inventory.

Docs/PersistenceDesignDocument.md

@@ -401,6 +401,14 @@ Do not store:
 Player records should store stable IDs and gameplay state, not sensitive
 account credentials.
 
+For the MVP `USaveGame` path, each saved player keeps both a backwards-compatible
+`PlayerId` string and an `FAgrarianSavedPlayerIdentity` block. The stable ID
+prefers the replicated `APlayerState` unique network ID when one exists, then
+falls back to player name, then pawn name for local prototype sessions. The
+identity block also records the display player name, raw network ID, whether
+the network ID was used, and the last known pawn name. It deliberately does not
+store passwords, tokens, emails, or platform credentials.
+
 ## Testing Gates
 
 Minimum persistence smoke test:

Scripts/verify_player_identity_persistence.py

@@ -0,0 +1,51 @@
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[1]
+
+EXPECTED = {
+    ROOT / "Source" / "AgrarianGame" / "AgrarianSaveGame.h": [
+        "struct FAgrarianSavedPlayerIdentity",
+        "FString StablePlayerId;",
+        "FString PlayerName;",
+        "FString NetworkId;",
+        "bool bUsedNetworkId = false;",
+        "FAgrarianSavedPlayerIdentity Identity;",
+    ],
+    ROOT / "Source" / "AgrarianGame" / "AgrarianPersistenceSubsystem.cpp": [
+        "SavedPlayer.Identity.StablePlayerId = SavedPlayer.PlayerId;",
+        "SavedPlayer.Identity.LastKnownPawnName = Character->GetName();",
+        "SavedPlayer.Identity.PlayerName = PlayerState->GetPlayerName();",
+        "SavedPlayer.Identity.NetworkId = UniqueId->ToString();",
+        "SavedPlayer.Identity.bUsedNetworkId = true;",
+        "return UniqueId->ToString();",
+    ],
+    ROOT / "Docs" / "PersistenceDesignDocument.md": [
+        "`FAgrarianSavedPlayerIdentity`",
+        "prefers the replicated `APlayerState` unique network ID",
+        "store passwords, tokens, emails, or platform credentials",
+    ],
+    ROOT / "AGRARIAN_DEVELOPMENT_ROADMAP.md": [
+        "[x] Save player identity.",
+        "`FAgrarianSavedPlayerIdentity`",
+        "without storing credentials",
+    ],
+}
+
+
+def main() -> None:
+    missing = []
+    for path, snippets in EXPECTED.items():
+        text = path.read_text(encoding="utf-8")
+        for snippet in snippets:
+            if snippet not in text:
+                missing.append(f"{path.relative_to(ROOT)}: {snippet}")
+
+    if missing:
+        raise RuntimeError("Player identity persistence verification failed: " + "; ".join(missing))
+
+    print("PASS: player identity persistence captures safe stable identity metadata.")
+
+
+if __name__ == "__main__":
+    main()

Source/AgrarianGame/AgrarianPersistenceSubsystem.cpp

@@ -326,6 +326,18 @@ bool UAgrarianPersistenceSubsystem::CapturePlayerIntoSave(const AAgrarianGameCha
 
 	FAgrarianSavedPlayer SavedPlayer;
 	SavedPlayer.PlayerId = GetPlayerPersistenceId(Character);
+	SavedPlayer.Identity.StablePlayerId = SavedPlayer.PlayerId;
+	SavedPlayer.Identity.LastKnownPawnName = Character->GetName();
+	if (const APlayerState* PlayerState = Character->GetPlayerState())
+	{
+		SavedPlayer.Identity.PlayerName = PlayerState->GetPlayerName();
+		const FUniqueNetIdRepl& UniqueId = PlayerState->GetUniqueId();
+		if (UniqueId.IsValid())
+		{
+			SavedPlayer.Identity.NetworkId = UniqueId->ToString();
+			SavedPlayer.Identity.bUsedNetworkId = true;
+		}
+	}
 	SavedPlayer.Transform = Character->GetActorTransform();
 	SavedPlayer.Survival = SurvivalComponent->Survival;
 	SavedPlayer.CareHistory = SurvivalComponent->CareHistory;
@@ -448,6 +460,12 @@ FString UAgrarianPersistenceSubsystem::GetPlayerPersistenceId(const AAgrarianGam
 
 	if (const APlayerState* PlayerState = Character->GetPlayerState())
 	{
+		const FUniqueNetIdRepl& UniqueId = PlayerState->GetUniqueId();
+		if (UniqueId.IsValid())
+		{
+			return UniqueId->ToString();
+		}
+
 		const FString PlayerName = PlayerState->GetPlayerName();
 		if (!PlayerName.IsEmpty())
 		{

Source/AgrarianGame/AgrarianSaveGame.h

@@ -7,6 +7,27 @@
 #include "AgrarianTypes.h"
 #include "AgrarianSaveGame.generated.h"
 
+USTRUCT(BlueprintType)
+struct FAgrarianSavedPlayerIdentity
+{
+	GENERATED_BODY()
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Save")
+	FString StablePlayerId;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Save")
+	FString PlayerName;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Save")
+	FString NetworkId;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Save")
+	bool bUsedNetworkId = false;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Save")
+	FString LastKnownPawnName;
+};
+
 USTRUCT(BlueprintType)
 struct FAgrarianSavedPlayer
 {
@@ -15,6 +36,9 @@ struct FAgrarianSavedPlayer
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Save")
 	FString PlayerId;
 
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Save")
+	FAgrarianSavedPlayerIdentity Identity;
+
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Save")
 	FTransform Transform;