Fix Wrong Kernel version Shown when Backup is done if fastboot boot is used

This works only on certain devices. Most devices stores fastboot booted kernel in RAM only.
Still this code refactors that part of code to a better format.

Author: fatalcoder524

app/src/main/java/com/github/capntrips/kernelflasher/ui/screens/slot/SlotViewModel.kt

@@ -459,17 +459,16 @@ class SlotViewModel(
         return backupDir
     }
 
+    @OptIn(ExperimentalSerializationApi::class)
     fun backup(context: Context) {
         launch {
             _clearFlash()
-            val currentKernelVersion = if (_slotInfo.value.bootImgInfo.kernelVersion != null) {
-                _slotInfo.value.bootImgInfo.kernelVersion
-            } else if (isActive) {
-                System.getProperty("os.version")!!
-            } else {
+
+            val currentKernelVersion = _slotInfo.value.bootImgInfo.kernelVersion ?: run {
                 _getKernel(context)
-                _slotInfo.value.bootImgInfo.kernelVersion
+                _slotInfo.value.bootImgInfo.kernelVersion ?: System.getProperty("os.version")!!
             }
+
             val now = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd--HH-mm"))
             val backupDir = createBackupDir(context, now)
             addMessage("Saving backup $now")
@@ -484,9 +483,11 @@ class SlotViewModel(
             _backups[now] = backup
             addMessage("Backup $now saved")
             _wasFlashSuccess.value = true
+            SharedViewModels.mainViewModel.markRefreshNeeded()
         }
     }
 
+    @OptIn(ExperimentalSerializationApi::class)
     fun backupZip(context: Context, callback: () -> Unit) {
         launch {
             val source = context.contentResolver.openInputStream(flashUri!!)
@@ -511,6 +512,7 @@ class SlotViewModel(
             } else {
                 log(context, "AK3 zip is missing", shouldThrow = true)
             }
+            SharedViewModels.mainViewModel.markRefreshNeeded()
         }
     }