v168

[bretth18]

Description

This PR makes the following changes for version 1.6.8:

• fix/improve settings persistence
• improve concurrency (remove old Combine usage)
• added scrobble retry queue (max 50) for failed scrobbles / offline
• cache lastFM friend data
• HIG improvements, reduce motion support
• tests updated

How to test

• ensure all checks pass

Author checklist

This PR:

• Satisfies a goal that is specific & clearly motivated
• Adds value in isolation (whether user-facing or sustainability-related)
• Contains a concise & easy-to-understand title + description
• Adheres to SRP by default
• Presents the best possible implementation to meet its goal, given constraints at hand