fix: handle stopped runner detachment and initial speed callback

Agent-Logs-Url: https://github.com/bedaHovorka/interlockSim/sessions/e88ff78a-7a85-4ecd-9542-da0b8e356164

Co-authored-by: bedaHovorka <5263405+bedaHovorka@users.noreply.github.com>

Author: Copilot

desktop-ui/src/main/kotlin/cz/vutbr/fit/interlockSim/gui/Frame.kt

@@ -127,6 +127,7 @@ class Frame : JFrame(PROGRAM_FULL_NAME) {
 
 						SimulationController.SimulationStatus.STOPPED -> {
 							toolBar.hideSimulationControls()
+							simulationControlPanel.runner = null
 							controlPanel.setStopEnabled(false)
 							controlPanel.updateStatus(ControlPanel.SimulationStatus.STOPPED)
 						}

desktop-ui/src/main/kotlin/cz/vutbr/fit/interlockSim/gui/SimulationController.kt

@@ -112,6 +112,7 @@ internal class SimulationController(
 		}
 		speedListener = listener
 		newRunner.addPropertyChangeListener(SimulationRunner.PROP_SPEED_MULTIPLIER, listener)
+		onSpeedChanged(newRunner.speedMultiplier)
 
 		onStateChanged(SimulationStatus.RUNNING)
 

desktop-ui/src/test/kotlin/cz/vutbr/fit/interlockSim/gui/SimulationControllerTest.kt

@@ -519,6 +519,33 @@ class SimulationControllerTest {
 		controller.stop()
 	}
 
+	@Test
+	@Timeout(value = 10, unit = TimeUnit.SECONDS)
+	@DisplayName("preselected speed is propagated to StatusBar when start() begins")
+	fun preselectedSpeedPropagatesOnStart() {
+		val started = CountDownLatch(1)
+		val blockSim = CountDownLatch(1)
+		every { context.run() } answers {
+			started.countDown()
+			blockSim.await(10, TimeUnit.SECONDS)
+		}
+
+		val statusBar = StatusBar()
+		val controller = createController(statusBar = statusBar)
+		controller.setSpeed(2.5)
+		controller.start(context)
+		assertThat(started.await(5, TimeUnit.SECONDS)).isTrue()
+		flushEDT()
+
+		SwingUtilities.invokeAndWait {
+			assertThat(statusBar.speedIndicatorText()).isEqualTo("Speed: 2.5x")
+			assertThat(statusBar.isSpeedIndicatorVisible()).isTrue()
+		}
+
+		blockSim.countDown()
+		controller.stop()
+	}
+
 	// ── helpers ───────────────────────────────────────────────────────────────
 
 	// ── toolBar / statusBar wiring ────────────────────────────────────────────