Step 2: the telemetry seam

ITelemetrySink with the null, log and JSON Lines sinks, FTelemetryEvent and the envelope, TelemetryEvents,
UTelemetrySubsystem on the game instance, ASaltyGameMode minting the session id into the replicated
ASaltyGameState, bs.TelemetryTest, the git hash in the build string (D-42) and four Salty.Core.Telemetry tests
replacing the placeholder. Proved standalone and with a headless server plus client sharing one session id.

Also enables the engine's Editor, AutomationTest, GameplayTags, ConfigSettings and LiveCoding MCP toolsets
(D-43) so the editor's MCP server exposes more than the skills toolset.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

Source/Salty/Salty.Build.cs

@@ -27,7 +27,11 @@ public class Salty : ModuleRules
 			"Slate"
 		});
 
-		PrivateDependencyModuleNames.AddRange(new string[] { });
+		PrivateDependencyModuleNames.AddRange(new string[] { "Json" });
+
+		// The telemetry envelope's build string carries the git hash. Read here at build time; a new commit
+		// changes the definition and rebuilds this module, which is the price of never lying about the build.
+		PrivateDefinitions.Add("SALTY_GIT_HASH=\"" + ReadGitHash() + "\"");
 
 		PublicIncludePaths.AddRange(new string[] {
 			"Salty",
@@ -55,4 +59,32 @@ public class Salty : ModuleRules
 
 		// To include OnlineSubsystemSteam, add it to the plugins section in your uproject file with the Enabled attribute set to true
 	}
+
+	private string ReadGitHash()
+	{
+		try
+		{
+			var StartInfo = new System.Diagnostics.ProcessStartInfo("git", "rev-parse --short HEAD")
+			{
+				WorkingDirectory = ModuleDirectory,
+				RedirectStandardOutput = true,
+				RedirectStandardError = true,
+				UseShellExecute = false,
+				CreateNoWindow = true
+			};
+			using (var Process = System.Diagnostics.Process.Start(StartInfo))
+			{
+				string Output = Process.StandardOutput.ReadToEnd().Trim();
+				Process.WaitForExit();
+				if (Process.ExitCode == 0 && Output.Length > 0)
+				{
+					return Output;
+				}
+			}
+		}
+		catch (System.Exception)
+		{
+		}
+		return "nogit";
+	}
 }