support for poetry and epigraphs

composeApp/src/jvmMain/kotlin/net/sergeych/toread/BookPlatform.jvm.kt

@@ -312,9 +312,15 @@ actual suspend fun viewLibraryBookFile(fileId: String): Boolean = withContext(Di
 actual suspend fun loadBookInfoExtras(fileId: String): BookInfoExtras = withContext(Dispatchers.IO) {
     openLibraryDatabase().useLibrary { db ->
         val file = db.files.get(fileId) ?: return@useLibrary BookInfoExtras()
-        val clusterId = file.bodyClusterId ?: return@useLibrary BookInfoExtras()
+        val sourceFileName = file.originalFilename ?: file.storageUri?.substringAfterLast(File.separatorChar)
+        val clusterId = file.bodyClusterId ?: return@useLibrary BookInfoExtras(
+            sourceFileName = sourceFileName,
+            sourceFilePath = file.storageUri,
+        )
         val readingPosition = db.readingStates.getForBodyCluster(clusterId)?.anchor?.formatHintsJson?.toReadingPosition()
         BookInfoExtras(
+            sourceFileName = sourceFileName,
+            sourceFilePath = file.storageUri,
             bookmarks = db.bookmarks.listForBodyCluster(clusterId).map {
                 BookmarkInfo(
                     title = it.title,