Separate Logistical Code from UI Code in SchedulingActivity

ideally the logistical code is separated from the ui code thru a method call, where the logic code can live in the presenter and the ui code lives in the activity. combining both makes the file more difficult to read -- this is just one ex of the need for a presenter in this file

_Originally posted by @ningning621 in https://github.com/cuappdev/pear-android/pull/3_

Start by reading SchedulingActivity and identify which code handles scheduling logic versus UI responsibilities. Define the presenter boundary described in the issue, move the logistical work behind method calls, and verify that the activity remains responsible for UI behavior without changing scheduling functionality.

索引モデルが issue の本文から書いたものです。