Added modes: Tridoku, Hoshi Sudoku

Added Practice Mode support for all Sudoku variants

Workshop: all 9x9 Sudoku variants now support visual editing; all Sudoku types now support JSON import and editing

Added: Print to PDF — export the current puzzle as a PDF with optional progress, drafts, and solution

Added: Frame Sudoku border numbers now support click-to-toggle display (normal/dimmed) for manually excluding reasoned clues

Added: New / Beta badges on mode selection cards to highlight recently added and in-testing variants

Added: User feedback entry on the home page