RTL support? (OS X, too)

From a user:

`I use simplenote on Mac and iOS. Both systems have native support for rtl (right to left) languages, In my case it's Arabic. Simplenote on both systems doesn't keep the text on the right as it should be for a rtl text. I could set the direction to rtl from the menu (in iOS) but it gets back to the left side after leaving the app. On Mac it’s not possible to set the note to RTL direction. I hope it’s a bug that could fixed. I really like the app, this is the only reason i didn’t fully switch to Simplenote.`

Opened by @roundhill

Start by reproducing the reported RTL behavior in the iOS app, including the direction setting reverting after leaving a note. Compare this with the reported macOS behavior and trace the note editing and direction-setting entry points. Done means Arabic and other right-to-left text remains right-aligned after leaving and reopening a note, with the supported platform scope verified.

Written by the indexing model from the issue text.