Refactors AdminGameDetail to use tabs instead of stacked sections,
adds GET /export/games/{game_id}/bosses endpoint, and adds Export
button to the Boss Battles tab.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Backend export endpoints return DB data in seed JSON format
(games, routes+encounters, pokemon, evolutions). Frontend
downloads the JSON via new Export buttons on each admin page.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
