Add type restriction rule (monolocke)

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>

backend/src/app/seeds/inject_test_data.py

@@ -154,6 +154,7 @@ DEFAULT_RULES = {
     "egglocke": False,
     "wonderlocke": False,
     "randomizer": False,
+    "allowedTypes": [],
 }