fix(cli): restart stale clients after updates

packages/client/test/service.test.ts

@@ -0,0 +1,49 @@
+import { NodeFileSystem } from "@effect/platform-node"
+import { afterEach, expect, test } from "bun:test"
+import { Effect } from "effect"
+import fs from "node:fs/promises"
+import os from "node:os"
+import path from "node:path"
+import { Service } from "../src/effect/index"
+
+const cleanup: Array<() => void | Promise<void>> = []
+
+afterEach(async () => {
+  await Promise.all(cleanup.splice(0).map(async (run) => await run()))
+})
+
+test("does not start or stop a healthy service rejected by the version policy", async () => {
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-client-service-"))
+  const child = Bun.spawn([process.execPath, "-e", "await new Promise(() => {})"])
+  const server = Bun.serve({ port: 0, fetch: () => Response.json({ healthy: true }) })
+  const file = path.join(root, "service.json")
+  cleanup.push(
+    () => child.kill(),
+    () => server.stop(true),
+    () => fs.rm(root, { recursive: true, force: true }),
+  )
+  await Bun.write(file, JSON.stringify({ id: "newer", version: "2.0.0", url: server.url.toString(), pid: child.pid }))
+
+  const options = {
+    file,
+    version: "1.0.0",
+    canReplace: () => false,
+    command: [process.execPath, "-e", "throw new Error('should not spawn')"],
+  }
+  const startError = await Service.start(options).pipe(
+    Effect.flip,
+    Effect.provide(NodeFileSystem.layer),
+    Effect.runPromise,
+  )
+  const stopError = await Service.stop(options).pipe(
+    Effect.flip,
+    Effect.provide(NodeFileSystem.layer),
+    Effect.runPromise,
+  )
+
+  expect(startError).toBeInstanceOf(Service.VersionMismatchError)
+  expect(startError).toMatchObject({ clientVersion: "1.0.0", serverVersion: "2.0.0" })
+  expect(stopError).toBeInstanceOf(Service.VersionMismatchError)
+  expect(process.kill(child.pid, 0)).toBe(true)
+  expect(await Bun.file(file).exists()).toBe(true)
+})