Adds allowedTypes: string[] to NuzlockeRules. When set, the encounter
selector hides non-matching Pokemon and the routes endpoint filters out
routes with no matching encounters, so only eligible locations appear.
Type picker UI in RulesConfiguration; active restriction shown in
RuleBadges. Backend accepts allowed_types query param and joins through
RouteEncounter.pokemon to filter by type.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>