feat: v3 — fight loop, expanded challenges, FightPage ownership guard

- Add fight-loop CLI for automated mock fights with elo-based matchmaking
- Expand challenge types, scoring narrations, arenas, and mock bot pool
- FightPage "Fight again" buttons now only show for your own bot
- FightViewer async scene init, live fight polling with round counter
- Extract mock answers into separate answers module

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

server/src/engine/orchestrator.ts

@@ -80,7 +80,14 @@ async function callWebhook(
       return { answer: null, timeMs: elapsed, timedOut: false, error: true }
     }
 
-    const data = await res.json() as { answer?: string; trash_talk?: string }
+    const text = await res.text()
+    let data: { answer?: string; trash_talk?: string }
+    try {
+      data = JSON.parse(text)
+    } catch {
+      console.log(`[webhook] ${url} returned non-JSON in ${elapsed}ms: ${text.slice(0, 200)}`)
+      return { answer: null, timeMs: elapsed, timedOut: false, error: true }
+    }
     console.log(`[webhook] ${url} OK in ${elapsed}ms answer=${(data.answer || '').slice(0, 80)}`)
     return {
       answer: data.answer || null,
@@ -115,7 +122,7 @@ async function getBotResponse(
 ): Promise<WebhookResponse> {
   if (isMockBot(bot.webhookUrl)) {
     console.log(`[fight] ${bot.name} is mock bot, generating response`)
-    const mock = generateMockBotResponse(challenge.type, bot.name)
+    const mock = generateMockBotResponse(challenge, bot.name)
     return {
       answer: mock.answer || null,
       trashTalk: mock.trashTalk,