Enforce Dupes Clause and Shiny Clause rules

Dupes Clause greys out Pokemon in the encounter modal whose evolution
family has already been caught, preventing duplicate selections. Shiny
Clause adds a dedicated Shiny Box and lets shiny catches bypass the
one-per-route lock via a new is_shiny column on encounters and a
/pokemon/families endpoint that computes evolution family groups.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/types/game.ts

@@ -59,6 +59,7 @@ export interface Encounter {
   catchLevel: number | null
   faintLevel: number | null
   deathCause: string | null
+  isShiny: boolean
   caughtAt: string
 }
 
@@ -115,6 +116,7 @@ export interface CreateEncounterInput {
   nickname?: string
   status: EncounterStatus
   catchLevel?: number
+  isShiny?: boolean
 }
 
 export interface UpdateEncounterInput {