Add a safe check before before we start writing logs

[rahul-lohra]

🎯 Goal

Resolve file unavailable crash, specially on Chinesse OEMs

Fatal Exception: java.io.FileNotFoundException: /mnt/expand/d741f19b-cac4-44ef-aa92-e8c0402a1b3b/user/0/<packagename>/files/internal_0.txt: open failed: EINVAL (Invalid argument)
       at [libcore.io](http://libcore.io/).IoBridge.open(IoBridge.java:574)
       at [java.io](http://java.io/).FileOutputStream.<init>(FileOutputStream.java:259)
       at io.getstream.log.file.FileStreamLoggerKt.fileWriter(FileStreamLogger.kt:163)
       at io.getstream.log.file.FileStreamLoggerKt.access$fileWriter(FileStreamLogger.kt:1)
       at io.getstream.log.file.FileStreamLogger.initIfNeeded(FileStreamLogger.kt:105)
       at io.getstream.log.file.FileStreamLogger.log$lambda$1(FileStreamLogger.java:69)
       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:644)
       at java.lang.Thread.run(Thread.java:1012)

   * On some Android 11+ devices (especially Chinese OEMs), we observed that creating files
   * using File(...) and createNewFile() can fail unexpectedly (background/doze modes/RAM cleaning/device cleanup utilities) with FileNotFoundException or EINVAL,
   * even when writing to internal storage.
   * This helper ensures safe creation of files by handling edge cases and logging issues to improve
   * stability across all devices.

🛠 Implementation details

Check if file exists and is writable before we start writing to it