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>

frontend/src/components/RuleBadges.tsx

@@ -1,5 +1,6 @@
 import type { NuzlockeRules } from '../types'
 import { RULE_DEFINITIONS } from '../types/rules'
+import { TypeBadge } from './TypeBadge'
 
 interface RuleBadgesProps {
   rules: NuzlockeRules
@@ -7,8 +8,9 @@ interface RuleBadgesProps {
 
 export function RuleBadges({ rules }: RuleBadgesProps) {
   const enabledRules = RULE_DEFINITIONS.filter((def) => rules[def.key])
+  const allowedTypes = rules.allowedTypes ?? []
 
-  if (enabledRules.length === 0) {
+  if (enabledRules.length === 0 && allowedTypes.length === 0) {
     return <span className="text-sm text-text-tertiary">No rules enabled</span>
   }
 
@@ -29,6 +31,17 @@ export function RuleBadges({ rules }: RuleBadgesProps) {
           {def.name}
         </span>
       ))}
+      {allowedTypes.length > 0 && (
+        <span
+          title={`Type restriction: ${allowedTypes.map((t) => t.charAt(0).toUpperCase() + t.slice(1)).join(', ')}`}
+          className="px-2 py-0.5 rounded-full text-xs font-medium bg-amber-900/40 text-amber-300 light:bg-amber-100 light:text-amber-700 flex items-center gap-1"
+        >
+          <span>Type Restriction</span>
+          {allowedTypes.map((t) => (
+            <TypeBadge key={t} type={t} size="sm" />
+          ))}
+        </span>
+      )}
     </div>
   )
 }