feat(ui): top-right 日程按钮 — add current/next pass to system calendar on radar and passes pages

Restores the original repo's calendar function (ic_calendar → AddToCalendar via
CalendarContract ACTION_INSERT) to the top-right of both pages, replacing the
map buttons:
- Radar page: back to upstream's addToCalendar (current pass name/aos/los).
- Passes page: new PassesAction.AddToCalendar wired through PassesViewModel +
  container.provideAddToCalendar() (next pass name/aos/los); left button back
  to the pass filter (reverts the earlier radios-button swap).
The map button is gone from both top bars — the map is now a bottom-nav tab.
Also drops the now-dead openMapRequest/navigateToMap navigation chain in
NavRoot/MainScreen that only the radar map button used.

feature/radar/src/main/java/com/rtbishop/look4sat/feature/radar/RadarScreen.kt

@@ -84,7 +84,7 @@ private enum class RadarPage(val title: String) {
 }
 
 @Composable
-fun RadarDestination(navigateUp: () -> Unit, navigateToMap: () -> Unit) {
+fun RadarDestination(navigateUp: () -> Unit) {
     val context = LocalContext.current
     val container = (context.applicationContext as IContainerProvider).getMainContainer()
     val viewModel: RadarViewModel = viewModel(factory = RadarViewModel.factory(container))
@@ -96,12 +96,6 @@ fun RadarDestination(navigateUp: () -> Unit, navigateToMap: () -> Unit) {
         }
         navigateUp()
     }
-    val navigateToMapAndClearMutual = {
-        if (container.mutualPassData.value.endTime > 0L) {
-            container.setMutualPassData(MutualPassData())
-        }
-        navigateToMap()
-    }
     LaunchedEffect(mutualData.endTime) {
         if (mutualData.endTime <= 0L) return@LaunchedEffect
         while (true) {
@@ -127,7 +121,7 @@ fun RadarDestination(navigateUp: () -> Unit, navigateToMap: () -> Unit) {
         viewModel.onAction(RadarAction.SstvPermissionResult(granted))
         viewModel.onAction(RadarAction.CwPermissionResult(granted))
     }
-    RadarScreen(uiState, viewModel::onAction, navigateUpAndClearMutual, navigateToMapAndClearMutual, mutualData, requestMicPermission = {
+    RadarScreen(uiState, viewModel::onAction, navigateUpAndClearMutual, mutualData, requestMicPermission = {
         permissionLauncher.launch(Manifest.permission.RECORD_AUDIO)
     })
 }
@@ -137,11 +131,14 @@ private fun RadarScreen(
     uiState: RadarState,
     onAction: (RadarAction) -> Unit,
     navigateUp: () -> Unit,
-    navigateToMap: () -> Unit,
     mutualData: MutualPassData,
     requestMicPermission: () -> Unit
 ) {
     val upcomingPass = uiState.currentPass ?: getDefaultPass()
+    // 日程功能: 把当前过境写入系统日历(原仓库的 addToCalendar, ic_calendar 按钮)
+    val addToCalendar: () -> Unit = {
+        uiState.currentPass?.let { onAction(RadarAction.AddToCalendar(it.name, it.aosTime, it.losTime)) }
+    }
     // Station-B overlay: full track line (only where B's elevation > 0) + live position dot
     // at the current moment, same display mode as the local station.
     val trackB = remember(mutualData.trackSamples) {
@@ -177,7 +174,7 @@ private fun RadarScreen(
             TopBar {
                 IconCard(action = navigateUp, resId = R.drawable.ic_back)
                 TimerRow(timeString = uiState.currentTime, isTimeAos = uiState.isTimeAos)
-                IconCard(action = navigateToMap, resId = R.drawable.ic_map)
+                IconCard(action = addToCalendar, resId = R.drawable.ic_calendar)
             }
             TopBar { NextPassRow(pass = upcomingPass, isUtc = uiState.isUtc) }
         } else {
@@ -185,7 +182,7 @@ private fun RadarScreen(
                 IconCard(action = navigateUp, resId = R.drawable.ic_back)
                 TimerRow(timeString = uiState.currentTime, isTimeAos = uiState.isTimeAos)
                 NextPassRow(pass = upcomingPass, modifier = Modifier.weight(1f), isUtc = uiState.isUtc)
-                IconCard(action = navigateToMap, resId = R.drawable.ic_map)
+                IconCard(action = addToCalendar, resId = R.drawable.ic_calendar)
             }
         }
         if (isVertical) {