Update default parameter for singleRunStrategy to ToolCalls.SEQUENTIAL.

Author: devcrocod

agents/agents-core/src/commonMain/kotlin/ai/koog/agents/core/agent/AIAgentSimpleStrategies.kt

@@ -30,7 +30,7 @@ import ai.koog.agents.core.dsl.extension.onToolCall
  *                - SingleRunMode.PARALLEL: Executes multiple tool calls in parallel.
  * @return An instance of AIAgentStrategy configured according to the specified single-run mode.
  */
-public fun singleRunStrategy(runMode: ToolCalls = ToolCalls.SINGLE_RUN_SEQUENTIAL): AIAgentGraphStrategy<String, String> =
+public fun singleRunStrategy(runMode: ToolCalls = ToolCalls.SEQUENTIAL): AIAgentGraphStrategy<String, String> =
     when (runMode) {
         ToolCalls.SEQUENTIAL -> singleRunWithParallelAbility(false)
         ToolCalls.PARALLEL -> singleRunWithParallelAbility(true)