refactor: extract shared FightData interface to fight/types.ts

Move FightData, FightRound, FightBot, FightArenaInfo types from local
definitions in FightViewer.vue to shared fight/types.ts. Replace `any`
typing in HumanFightPage, FightPage, useFightPolling, and useFightCache
with proper typed interfaces. Fix null-safety guards exposed by typing.

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

frontend/src/game/fight/types.ts

@@ -2,6 +2,8 @@ import type kaplay from 'kaplay'
 import type { GameObj, SpriteComp, PosComp, ScaleComp, AnchorComp, OpacityComp, ColorComp, RotateComp, ZComp } from 'kaplay'
 import type { SpriteCustomization } from '../sprites'
 
+export type { SpriteCustomization }
+
 export type Fighter = GameObj<SpriteComp | PosComp | ScaleComp | AnchorComp | OpacityComp | ColorComp | RotateComp | ZComp>
 
 export type KaplayInstance = ReturnType<typeof kaplay>
@@ -85,3 +87,56 @@ export interface RoundEvent {
   botAResponse?: string
   botBResponse?: string
 }
+
+// --- Shared fight data types (used across pages & composables) ---
+
+export interface FightRound {
+  roundNumber: number
+  challengeType: string
+  challengeData: string
+  botAResponse: string | null
+  botATimeMs: number | null
+  botAScore: number | null
+  botBResponse: string | null
+  botBTimeMs: number | null
+  botBScore: number | null
+  winnerId: string | null
+  narration: string | null
+}
+
+export interface FightBot {
+  id: string
+  name: string
+  avatarSeed: string
+  archetype?: string
+  customization?: SpriteCustomization | null
+  profilePicUrl?: string | null
+  eloRating: number
+  wins: number
+  losses: number
+  tier: number
+  botType?: string
+}
+
+export interface FightArenaInfo {
+  id: string
+  name: string
+  description: string
+  modifier: string | null
+}
+
+export interface FightData {
+  id: string
+  botAId: string
+  botBId: string
+  botA: FightBot | null
+  botB: FightBot | null
+  arenaInfo: FightArenaInfo | null
+  arena: string
+  winnerId: string | null
+  botAHp: number
+  botBHp: number
+  totalRounds: number
+  status: string
+  rounds: FightRound[]
+}