Fix taskbar updates for synced lyrics

[puohecbhad-bit]

Summary

• recognize SMTC bridges that publish synced lyrics through Title while preserving the original title - artist identity in Artist
• animate only the title for lyric updates and keep the taskbar widget layout, artwork, controls, and Next Up behavior tied to real track changes
• cache artwork work across lyric/playback updates and retry briefly after track changes when a bridge publishes the final thumbnail late without another media-property event

Why

Some SMTC lyric bridges replace the title for every lyric line and create fresh thumbnail references even when the artwork is unchanged. Treating every event as a new song caused the whole taskbar widget to re-enter, repeatedly decoded artwork, and showed Next Up for lyric lines. In addition, some bridges expose the new track before its final cover and do not always raise another event when the cover becomes available.

Validation

• built the GitHub Release|x64 MSIX bundle successfully (0 errors)
• manually tested with an SMTC bridge that updates the title for synced lyrics
• verified lyric lines only animate the title, artwork and controls remain stable, Next Up only appears for real tracks, and delayed artwork catches up after track changes