chore: remove all Twitch/streaming references

- Remove Twitch link from standings sidebar
- Delete scripts/stream-browser.ts (Twitch streaming script)
- Remove start:stream and start:stream:dryrun npm scripts
- Fix quipslop-export filename fallback in admin.tsx
- Fix hardcoded quipslop.sqlite in check-db.ts
- Rewrite README.md in Spanish, no Twitch mentions

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

package.json

@@ -5,10 +5,7 @@
   "private": true,
   "scripts": {
     "start": "bun server.ts",
-    "start:cli": "bun quipslop.tsx",
-    "start:web": "bun --hot server.ts",
-    "start:stream": "bun ./scripts/stream-browser.ts live",
-    "start:stream:dryrun": "bun ./scripts/stream-browser.ts dryrun"
+    "start:dev": "bun --hot server.ts"
   },
   "devDependencies": {
     "@types/bun": "latest",