refactor(android): resizeTextView cleanup

https://github.com/keymanapp/keyman/pull/14678#discussion_r2319397197

Keyman for Android and KMSample1 have `resizeTextView()` to adjust the textview height for status bar height, navigation bar height, and keyboard height.

Maybe we can refactor that into [KMTextView](https://github.com/keymanapp/keyman/blob/master/android/KMEA/app/src/main/java/com/keyman/engine/KMTextView.java).

Also, there's TODO's to cleanup going back to version 2.8

https://github.com/keymanapp/keyman/blame/e4683b75c37c6a362b9df4ade43124c14adb9a1c/android/KMAPro/kMAPro/src/main/java/com/tavultesoft/kmapro/MainActivity.java#L622-L626

Start with the linked pull-request discussion, then compare the resizeTextView implementations in Keyman for Android and KMSample1 with android/KMEA/app/src/main/java/com/keyman/engine/KMTextView.java. Review the TODOs in android/KMAPro/kMAPro/src/main/java/com/tavultesoft/kmapro/MainActivity.java, including the history link. Done means the resize logic is appropriately refactored into KMTextView and the identified cleanup is addressed.

Written by the indexing model from the issue text.