Enabling watch mode and configuring more than two useconfigs blocks compilation.

[Tarrowren]

Reproduction link or steps

tsdown: 0.20.1
windows: 11

tsdown.config.ts

import { defineConfig } from "tsdown";

export default defineConfig([
  {
    entry: ["src/index.ts"],
    outDir: "out1",
    platform: "node",
    target: "node22",
  },
  {
    entry: ["src/index.ts"],
    outDir: "out2",
    platform: "node",
    target: "node22",
  },
  {
    entry: ["src/index.ts"],
    outDir: "out3",
    platform: "node",
    target: "node22",
  },
]);

index.ts

console.log("hello");

npx tsdown -w

What is expected?

Successfully compiled

What is actually happening?

❯ npx tsdown -w
ℹ tsdown v0.20.1 powered by rolldown v1.0.0-rc.1
ℹ config file: C:\Users\faust\Desktop\jscode\lock-js\tsdown.config.ts 
ℹ entry: src\index.ts
ℹ target: node22
ℹ tsconfig: tsconfig.json
ℹ entry: src\index.ts
ℹ target: node22
ℹ tsconfig: tsconfig.json
ℹ entry: src\index.ts
ℹ target: node22
ℹ tsconfig: tsconfig.json
ℹ Build start  // blocking!!!

Any additional comments?

No response