feat(media_downloader): download the whole dash media

app/src/main/kotlin/me/rhunk/snapenhance/ui/manager/sections/downloads/DownloadsSection.kt

@@ -229,6 +229,7 @@ class DownloadsSection : Section() {
                         }
                         //open
                         FilledIconButton(onClick = {
+                            if (download.outputFile == null) return@FilledIconButton
                             val fileType = runCatching {
                                 context.androidContext.contentResolver.openInputStream(Uri.parse(download.outputFile))?.use { input ->
                                     FileType.fromInputStream(input)

core/src/main/kotlin/me/rhunk/snapenhance/features/impl/downloader/MediaDownloader.kt

@@ -364,6 +364,14 @@ class MediaDownloader : MessagingRuleFeature("MediaDownloader", MessagingRuleTyp
                             selectedChapters.remove(which)
                         }
                     }
+                    setNegativeButton("Cancel") { dialog, _ -> dialog.dismiss() }
+                    setNeutralButton("Download all") { _, _ ->
+                        provideDownloadManagerClient(
+                            mediaIdentifier = paramMap["STORY_ID"].toString(),
+                            downloadSource = MediaDownloadSource.PUBLIC_STORY,
+                            mediaAuthor = storyName
+                        ).downloadDashMedia(playlistUrl, 0, null)
+                    }
                     setPositiveButton("Download") { dialog, which ->
                         val groups = mutableListOf<MutableList<SnapChapterInfo>>()
                         var currentGroup = mutableListOf<SnapChapterInfo>()