chore: use DeepSeek for beta conflicts (#41669)

Co-authored-by: Luke Parker <10430890+Hona@users.noreply.github.com>

script/beta.ts

@@ -3,7 +3,7 @@
 import { $ } from "bun"
 import fs from "fs/promises"
 
-const model = "opencode/gpt-5.3-codex"
+const model = "opencode/deepseek-v4-flash"
 
 interface PR {
   number: number