Revert EMULATOR_MODE to rcon default, restore RCON config

src/lib/services/alert.ts

@@ -223,8 +223,10 @@ export function emulatorOffline(detail?: string): Promise<SendAlertResult> {
 		severity: "critical",
 		message: detail
 			? `Emulator appears offline: ${detail}`
-			: "Emulator appears offline — emulator API connection could not be established.",
+			: "Emulator appears offline — RCON connection could not be established.",
 		context: {
+			rconHost: env.RCON_HOST,
+			rconPort: env.RCON_PORT,
 			...(detail ? { detail } : {}),
 		},
 	});

src/lib/services/rcon.ts

@@ -225,20 +225,24 @@ export function httpTransport(opts: {
  * misconfiguration surfaces immediately instead of on first command.
  */
 export function createEmulatorTransport(): RconTransport {
-	const mode = env.EMULATOR_MODE ?? "api";
-	if (mode === "api") {
+	if (env.EMULATOR_MODE === "api") {
+		if (!env.EMULATOR_API_URL) {
+			throw new Error("EMULATOR_MODE=api requires EMULATOR_API_URL to be set");
+		}
 		return httpTransport({
-			url: env.EMULATOR_API_URL ?? "http://127.0.0.1:3001",
-			timeoutMs: 10_000,
+			url: env.EMULATOR_API_URL,
+			timeoutMs: env.RCON_TIMEOUT_MS,
 			apiKey: env.EMULATOR_API_KEY,
 			apiKeyHeader: env.EMULATOR_API_KEY_HEADER,
-			maxRetries: 3,
+			maxRetries: env.RCON_MAX_RETRIES,
 		});
 	}
-	// API mode only; RCON transport removed.
-	throw new Error(
-		"EMULATOR_MODE=rcon is no longer supported; use EMULATOR_MODE=api",
-	);
+	return tcpTransport({
+		host: env.RCON_HOST,
+		port: env.RCON_PORT,
+		timeoutMs: env.RCON_TIMEOUT_MS,
+		maxRetries: env.RCON_MAX_RETRIES,
+	});
 }
 
 const globalForRcon = globalThis as unknown as { rcon?: RconClient };