Disable Wanakana conversion on answer input

[DJTB]

User Request:

When entering answers I'm using handwriting input to write Kanji, however I have a problem where the input is corrupted before I can finish. For example if I enter "人" the first stroke is converted immediately to a "・" and then moves to the next character (clearing the handwriting input and therefore the chance of the second stroke). It's not 100% of the time, and some start strokes are worse than others.

I think the issue is a conflict between the handwriting keyboard and the script that converts alpha to hiragana. Normally the keyboard enters the first stroke into the textbox and then, on the subsequent strokes, modifies the character to the next predicted input (e.g. ー->ナ->大). For 人 I think that the keyboard entry starts the prediction with a "/" and then the input box script converts that to " ・" (can be replicated by typing / on normal keyboard).

This could be solved by adding a user (or inline quiz) setting that is on by default:
[ ] Convert Answer input to Romaji

This user could disable it since they always enter Japanese themselves.

[DJTB]

Basic implementation done: https://github.com/Kaniwani/kw-frontend/compare/optional-romaji-conversion.

TODO:

1. Persist to localstorage?
2. Add checkbox to Settings page and hook up to quiz?

It's probably fine to keep it as localstorage rather than saving to server. This means it would remain a per-device setting and it's minimal user effort to toggle it off again if they reinstall / clear cache etc.