[Wear OS] Enable rotary crown volume control on Now Playing screen

[kevinGC]

Rotating the physical crown on the Wear OS "Now Playing" screen previously had no effect on volume. Users had to navigate to the dedicated volume control screen to make volume adjustments.

Description

This change enables the crown to adjust volume, and displays a brief graphic when the volume changes. It uses Horologist's built-in rotary volume behavior and indicator.

Fixes #6128.

Testing Instructions

1. Build and install the Wear app on a Wear OS device with a rotary crown (e.g. Pixel Watch).
2. Open Pocket Casts on the watch and play any podcast episode.
3. On the Now Playing screen (the middle page with play/pause and skip controls), rotate the watch crown clockwise and counter-clockwise.
4. Verify that:
   • The media volume increases / decreases smoothly.
   • You feel subtle haptic clicks for each volume step.
   • The circular volume indicator briefly appears on the screen bezel and automatically disappears after ~2 seconds of inactivity.
5. Swipe to the Episode screen (page 0) and Up Next screen (page 2) and verify that crown scrolling still works as expected on those screens.

Checklist

All are done or not applicable.

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

I have tested any UI changes...

I don't think these apply to Wear, please correct me if I'm wrong.

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

[CLAassistant]

All committers have signed the CLA.