Add a setting to disable scrubbing on the lock screen

### Description

It would be great if there was an option to disable the playback scrubber on the lock screen.

Basically this is a request for implementing the same functionality as [https://github.com/Automattic/pocket-casts-ios/issues/2200](https://github.com/Automattic/pocket-casts-ios/issues/2200) recently added in the iOS version.

### Screenshots or screen recording

_No response_

### Did you search for existing list?

- [x] I have searched for existing issues.

Start by reading the linked iOS issue and tracing how the Android app exposes playback controls on the lock screen. Identify where user settings and the lock-screen scrubber are handled; done means a setting can disable the scrubber without removing other lock-screen controls.

Written by the indexing model from the issue text.