What was done

• Fixed 6 Xcode compiler warnings identified in the build
• Removed the entire legacy CoreData migration subsystem after confirming it was dead code

Warning fixes

• FollowingPlanetModel — suppressed unused result from MainActor.run returning a Task value
• Template (2 warnings) — removed redundant ?? nil on getNextPage/getPreviousPage which already return String?
• VideoInfoRow — added nonisolated to makeCompressionBackup(for:) since it only does file I/O but was MainActor-isolated and called from a detached task
• Planet+CoreDataProperties / PlanetArticle+CoreDataProperties — initially fixed by switching codegen to Manual/None, then removed entirely with the CoreData cleanup

CoreData removal

• Confirmed CoreData was only used by Saver.swift for a one-time migration from old CoreData persistence to current JSON format
• The migration path: PlanetAppDelegate.applicationDidFinishLaunching → Saver.isMigrationNeeded() → savePlanets() / migratePublic()
• No other code paths referenced CoreData classes

Files changed

• Planet/Entities/FollowingPlanetModel.swift — _ = Task { to suppress unused result
• Planet/TemplateBrowser/Template.swift — removed ?? nil wrapping
• Planet/Writer/VideoInfoRow.swift — added nonisolated to static method
• Planet/PlanetAppDelegate.swift — removed migration block
• Planet/Entities/PlanetStore.swift — removed isMigrating property
• Planet/Views/PlanetMainView.swift — removed migration progress sheet
• Planet.xcodeproj/project.pbxproj — removed all CoreData file references
• Planet/LegacyCoreData/ — deleted (Planet.swift, PlanetArticle.swift, CoreDataPersistence.swift)
• Planet/Planet.xcdatamodeld/ — deleted (7 model versions)
• Planet/Helper/Saver.swift — deleted
• Planet/Views/Saver/MigrationProgressView.swift — deleted