refactor: abstract SQLite behind runtime-conditional #db import (#18316)

packages/opencode/src/storage/db.bun.ts

@@ -0,0 +1,8 @@
+import { Database } from "bun:sqlite"
+import { drizzle } from "drizzle-orm/bun-sqlite"
+
+export function init(path: string) {
+  const sqlite = new Database(path, { create: true })
+  const db = drizzle({ client: sqlite })
+  return db
+}