Mobile: Buttons to hide completed & reverse sort episodes on podcast details view

[rudism]

This PR does the following, all quality-of-life enhancements/fixes to the mobile app for your consideration:

• Added SafeArea wrappers to the podcast and episode details pages so their content no longer draws under Android navigation bar at the bottom of the screen.
• Added some quick-action buttons under the search bar on podcast details to hide/show completed items and toggle ascending/descending episode date sorting.
  • Re: [Feature Request]: Mobile episode sort and filter #796
  • I think ultimately it would be nice to save this setting per podcast so that it remembers, and have more options aligned with the web ui, but I feel these buttons are a nice stop-gap to fill the need until a more thorough solution can be implemented
• Reduce padding under the "Episodes" heading on podcast details page.
• Fixed a bug on podcast details where "Mark as incomplete" wasn't working (it was always calling the "Mark as complete" action).
• Fixed background color of episode progress bar on podcast details to be consistent with what's used on the In Progress card on the home view.

Screenshot showing new buttons (icons toggle when clicked):