fix: fight restart bug, mobile TTS, character sizing, bitcoin symbols

- Fix fight replay showing empty scene: validate rounds before playing,
  retry loading fight data up to 5 times when rounds are missing
- Add COOP/COEP headers to production server for SharedArrayBuffer
  (required by Kokoro TTS WASM threading on mobile)
- Add blob: to scriptSrc/workerSrc CSP for Web Worker support
- Fix mobile character cutoff: raise ground line to 0.82, add
  MOBILE_SCALE_CAP (0.55) so fighters never shrink too small
- Add ₿ bitcoin chest badge to all fighter sprites (scales with tier)
- Add sats coin stack on bot profile page proportional to satsWon
- Seed dev tournament with 8 mock bots on startup (dev mode only)

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

server/src/index.ts

@@ -6,6 +6,7 @@ import { seedMockBots, seedClassicBots } from './engine/mock.js'
 import { startBackgroundFights } from './engine/background.js'
 import { getActiveFighterCount } from './engine/orchestrator.js'
 import { clearAllPending } from './engine/human-responses.js'
+import { seedDevTournament } from './engine/dev-seed.js'
 
 // Production env validation — warn but don't crash (wallet features degrade gracefully)
 if (process.env.NODE_ENV === 'production') {
@@ -24,6 +25,11 @@ runMigrations()
 await seedMockBots()
 await seedClassicBots()
 
+// Dev mode: seed tournament + betting data for testing
+if (process.env.NODE_ENV !== 'production') {
+  await seedDevTournament()
+}
+
 const port = Number(process.env.PORT) || 9100
 
 serve({ fetch: app.fetch, port }, () => {