Replaces the plain GridView with a Candy-Crush-style journey map:
dotted serpentine path, circular nodes (gold=done, glowing=current,
dark+lock=locked), glass header, auto-scroll to current stage.
Updates season_map_screen_test to use Key('stage_node_$i') finders.
SaveRepository (versioned JSON over prefs) with best-result merging and
unlock walking; ContentRepository loads the bundled pack; SeasonFlow/
Progress notifiers orchestrate stage start -> win record -> advance.
Season map grid with stars/locks, Home -> Map -> Game navigation,
close button, next-stage action on the win overlay.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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