refactor(discovery): improve KMP compatibility and clean up icon imports

- Replace platform-specific `String.format` with Kotlin standard library `padStart` in `DwellProgressIndicator` to support common code.
- Simplify fully qualified icon references in `DiscoveryGoogleMap` by adding explicit imports.

app/src/google/kotlin/org/meshtastic/app/map/discovery/DiscoveryGoogleMap.kt

@@ -38,6 +38,9 @@ import com.google.maps.android.compose.rememberCameraPositionState
 import com.google.maps.android.compose.rememberUpdatedMarkerState
 import org.meshtastic.core.ui.util.DiscoveryMapNode
 import org.meshtastic.core.ui.util.DiscoveryNeighborType
+import org.meshtastic.core.ui.icon.MeshtasticIcons
+import org.meshtastic.core.ui.icon.Person
+import org.meshtastic.core.ui.icon.Temperature
 
 private const val DEFAULT_ZOOM = 12f
 private const val BOUNDS_PADDING_PX = 100
@@ -115,9 +118,9 @@ fun DiscoveryGoogleMap(
                 }
             val nodeIcon =
                 if (node.isSensorNode) {
-                    org.meshtastic.core.ui.icon.MeshtasticIcons.Temperature
+                    MeshtasticIcons.Temperature
                 } else {
-                    org.meshtastic.core.ui.icon.MeshtasticIcons.Person
+                    MeshtasticIcons.Person
                 }
             MarkerComposable(
                 state = rememberUpdatedMarkerState(position = nodeLatLng),

feature/discovery/src/commonMain/kotlin/org/meshtastic/feature/discovery/ui/component/DwellProgressIndicator.kt

@@ -47,7 +47,7 @@ fun DwellProgressIndicator(
         }
     val minutes = remainingSeconds / SECONDS_PER_MINUTE
     val seconds = remainingSeconds % SECONDS_PER_MINUTE
-    val timeText = "%02d:%02d".format(minutes, seconds)
+    val timeText = "${minutes.toString().padStart(2, '0')}:${seconds.toString().padStart(2, '0')}"
 
     Column(verticalArrangement = Arrangement.spacedBy(CONTENT_PADDING), modifier = modifier.fillMaxWidth()) {
         Text(text = "Dwelling on $presetName", style = MaterialTheme.typography.titleSmall)