Added a small grace period to survival mechanic to allow easier start of the game.

Scripts/Tests/TestRunner.cs

@@ -12,6 +12,7 @@ public partial class TestRunner : Node
         Run("Inventory adds, stacks and removes items", TestInventoryStacksAndRemovesItems);
         Run("Inventory crafting checks stacked totals", TestInventoryCanCraftAcrossStacks);
         Run("Survival consumes stored food and water", TestSurvivalConsumesFoodAndWater);
+        Run("Survival grace period prevents early death", TestSurvivalGracePeriodPreventsEarlyDeath);
         Run("Survival death disables movement", TestSurvivalDeathDisablesMovement);
         Run("Robot research effects change robot stats", TestRobotResearchEffects);
         Run("Research completion applies effects once", TestResearchCompletionAppliesEffectsOnce);
@@ -21,6 +22,7 @@ public partial class TestRunner : Node
         Run("Resource extraction and save data roundtrip", TestResourceSaveRoundtrip);
         Run("Robot save data roundtrip keeps robot state", TestRobotSaveRoundtrip);
         Run("Save data captures and restores global state", TestSaveDataRestoresGlobalState);
+        Run("Save data restores survival timer", TestSaveDataRestoresSurvivalTimer);
         Run("Split save files store and load data", TestSplitSaveFilesRoundtrip);
         Run("Split save files include one file per saved layer", TestSplitSaveFilesIncludeLayerFiles);
         Run("If node evaluates inventory comparisons", TestIfNodeEvaluatesInventoryComparisons);
@@ -95,6 +97,7 @@ public partial class TestRunner : Node
     private void TestSurvivalDeathDisablesMovement()
     {
         GameData.canMove = true;
+        GameData.survival.gracePeriodEnabled = false;
         GameData.survival.energy = 0.01f;
 
         GameData.survival.Update(2.0);
@@ -103,6 +106,22 @@ public partial class TestRunner : Node
         AssertFalse(GameData.canMove, "movement should be disabled");
     }
 
+    private void TestSurvivalGracePeriodPreventsEarlyDeath()
+    {
+        GameData.canMove = true;
+        GameData.survival.hunger = 0f;
+        GameData.survival.thirst = 0f;
+        GameData.survival.energy = 0f;
+
+        GameData.survival.Update(1.0);
+
+        AssertFalse(GameData.survival.isDead, "survival should not fail during grace period");
+        AssertTrue(GameData.canMove, "movement should stay enabled during grace period");
+        AssertTrue(GameData.survival.hunger > 0f, "hunger should be clamped above zero");
+        AssertTrue(GameData.survival.thirst > 0f, "thirst should be clamped above zero");
+        AssertTrue(GameData.survival.energy > 0f, "energy should be clamped above zero");
+    }
+
     private void TestRobotResearchEffects()
     {
         RobotStats stats = new RobotStats();
@@ -202,6 +221,18 @@ public partial class TestRunner : Node
         AssertEqual(ResearchState.RESEARCHED, GameData.availableResearch["stoneage"].state, "saved research");
     }
 
+    private void TestSaveDataRestoresSurvivalTimer()
+    {
+        GameData.survival.elapsedSeconds = 321.5;
+
+        SaveGameData saveData = SaveGameManager.CreateSaveData();
+
+        GameData.ResetRunState();
+        SaveGameManager.ApplyWorldData(saveData);
+
+        AssertClose(321.5f, (float)GameData.survival.elapsedSeconds, 0.001f, "saved survival timer");
+    }
+
     private void TestResearchExecutionPaysResourcesAndFinishes()
     {
         GameData.inventory.AddItem(new Item { data = GameData.availableItems["stone"] }, 5);