Add missing auto play track events

[mebarbosa]

Description

This adds autoplay_started and autoplay_finished_last_episode track events

• autoplay_started: whenever an autoplay session starts
• autoplay_finished_last_episode: when the last episode of a playlist finishes playing

Fixes #2372

Testing Instructions

1. Go to settings -> General -> Enable AutoPlay toggle
2. Have some episodes starred
3. Go to Profile -> Starred
4. Play episodes from this list (Make sure you have empty Up next)
5. Scroll to finish the episode
6. The auto play will add an episode from the starred list
7. ✅ Ensure 🔵 Tracked: autoplay_started, Properties: {"episode_source":"starred" is triggered
8. Play the last episode from the starred list
9. Finish this episode
10. ✅ Ensure 🔵 Tracked: autoplay_finished_last_episode, Properties: {"episode_source":"starred" is triggered

You can repeat this test for filter list, download, podcast and file list if you wanted

Checklist

• [x] If this is a user-facing change, I have added an entry in CHANGELOG.md
• [x] Ensure the linter passes (./gradlew spotlessApply to automatically apply formatting/linting)
• [x] I have considered whether it makes sense to add tests for my changes
• [x] All strings that need to be localized are in modules/services/localization/src/main/res/values/strings.xml
• [x] Any jetpack compose components I added or changed are covered by compose previews
• [x] I have updated (or requested that someone edit) the spreadsheet to reflect any new or changed analytics.

I have tested any UI changes...

• [x] with different themes
• [x] with a landscape orientation
• [x] with the device set to have a large display and font size
• [x] for accessibility with TalkBack