Add back stack for deep link navigation (#1756)

## Description
When testing the new deep link feature from this PR
[#1688](https://github.com/damontecres/Wholphin/pull/1688)
I noticed that the back button would close the app. As in, all routes
are cleared and only the playback is in the nav stack.

I figured a more desirable behavior would be to create a nav stack,
always starting with the home screen, then also inserting the media
item's details page, if available.

To achieve this, I made the return Target.destinations a list of
destinations, and updated the other two uses in IntentService.

Open to implementation tweaks, or scrap it if this isn't how it should
work, haha.

### Testing

Tested deep links, which produced the following nav stacks:
- Movie view
  - Home → Movie details
- Movie playback (with and without position)
  - Home → Movie details → Playback
- Series view
  - Home → Series details
- Season view
  - Home → Season details
- Episode view
  - Home → Episode details
- Episode playback (with and without position)
  - Home → Episode details → Playback
- Trailer/extras playback (no details page available)
  - Home → Playback
- TV channel view
  - Home → Playback
- TV channel playback
  - Home → Playback

## AI or LLM usage
AI was used to generate the initial code, debug and test, then manual
refactoring and cleanup was done.

---------

Co-authored-by: Damontecres <damontecres@gmail.com>

app/src/main/java/com/github/damontecres/wholphin/MainActivity.kt

@@ -449,7 +449,14 @@ class MainActivityViewModel
                                 val current = serverRepository.current.value
                                 if (current != null) {
                                     Timber.i("Received valid intent, switching to AppContent")
-                                    navigationManager.replace(result.destination)
+
+                                    if (result.addHomeToBackStack) {
+                                        navigationManager.reloadHome()
+                                    } else {
+                                        navigationManager.backStack.clear()
+                                    }
+                                    navigationManager.backStack.addAll(result.destinations)
+
                                     setupNavigationManager.navigateTo(
                                         SetupDestination.AppContent(current),
                                     )

app/src/main/java/com/github/damontecres/wholphin/services/IntentService.kt

@@ -27,12 +27,11 @@ class IntentService
             Timber.v("Parsing intent %s", intent)
             Timber.v("Intent extras: %s", intent.extras)
             Timber.v("Intent data: %s", intent.data)
-            if (intent.getStringParam("type") != null) {
-                return getDestinationFromChannel(intent)?.let { IntentResult.Target(it) }
-                    ?: IntentResult.Error("Invalid parameters")
-            }
             val action = intent.action ?: intent.data?.host
-            if (action == Intent.ACTION_MAIN || action.isNullOrBlank()) {
+            if (
+                intent.getStringParam("type") == null &&
+                (action == Intent.ACTION_MAIN || action.isNullOrBlank())
+            ) {
                 return IntentResult.NoOp
             }
 
@@ -65,9 +64,19 @@ class IntentService
                 }
             }
 
+            if (intent.getStringParam("type") != null) {
+                return getDestinationFromChannel(intent)?.let {
+                    IntentResult.Target(
+                        destinations = listOf(it),
+                        addHomeToBackStack = false,
+                    )
+                }
+                    ?: IntentResult.Error("Invalid parameters")
+            }
+
             if (action == Intent.ACTION_SEARCH || action == "search") {
                 val query = intent.getStringParam(SearchManager.QUERY)
-                return IntentResult.Target(Destination.Search(query ?: ""))
+                return IntentResult.Target(listOf(Destination.Search(query ?: "")))
             }
             val itemId =
                 intent.getStringParam("itemId")?.toUUIDOrNull()
@@ -84,25 +93,39 @@ class IntentService
                     return IntentResult.Error("Could not fetch item $itemId")
                 }
 
-            val destination =
+            val itemDestination = item.destination()
+
+            val destinations =
                 when (action) {
                     Intent.ACTION_VIEW, "view" -> {
-                        item.destination()
+                        listOf(itemDestination)
                     }
 
                     "com.github.damontecres.wholphin.PLAYBACK", "play" -> {
                         val position = intent.getLongParam("position")?.coerceAtLeast(0)
-                        Destination.Playback(
+
-                            itemId = itemId,
+                        val playbackDestination =
-                            positionMs = position ?: 0L,
+                            Destination.Playback(
-                        )
+                                itemId = itemId,
+                                positionMs = position ?: 0L,
+                            )
+
+                        if (itemDestination is Destination.Playback) {
+                            listOf(playbackDestination)
+                        } else {
+                            listOf(
+                                itemDestination,
+                                playbackDestination,
+                            )
+                        }
                     }
 
                     else -> {
                         return IntentResult.Error("Invalid action: ${intent.action}")
                     }
                 }
-            return IntentResult.Target(destination)
+
+            return IntentResult.Target(destinations)
         }
 
         private fun Intent.getStringParam(key: String) = getStringExtra(key) ?: data?.getQueryParameter(key)
@@ -159,6 +182,7 @@ sealed interface IntentResult {
     data object NoOp : IntentResult
 
     data class Target(
-        val destination: Destination,
+        val destinations: List<Destination>,
+        val addHomeToBackStack: Boolean = true,
     ) : IntentResult
 }