ALTAPPS-950: Android make code editor an active input

[XanderZhu]

YouTrack Issues:
ALTAPPS-950

Checklist

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Description

• Extract keyboard extension logic from CodeStepQuizFullScreenDialogFragment to reuse it in CodeStepQuizFragment;
• Make codeEditor active input in CodeStepQuizFragment;
• Update code quiz UI;
• Replace SqlStepQuizFragment with CodeStepQuizFragment.

[ivan-magda]

When a problem is in a terminal state (successful submission or wrong, ...) user should not have the ability to navigate to the full-screen code editor, otherwise it can modify reply and submit it.

No bottom padding

optional (tiny suggestion)

Keyboard input accessory buttons overlap the cursor. You can reproduce this by tapping the "new line" button multiple times.

[XanderZhu]

@ivan-magda
It wouldn't be fast to implement auto scroll so that Keyboard input accessory buttons are not overlapping codeEditor.
It's possible now for users to scroll manually. We can implement this feature later.