fix(tests): stabilize auto-update-checker isolation under bun

src/hooks/auto-update-checker/hook.test.ts

@@ -1,4 +1,4 @@
-import { describe, it, expect, mock } from "bun:test"
+import { afterEach, describe, it, expect, mock } from "bun:test"
 
 const mockShowConfigErrorsIfAny = mock(async () => {})
 const mockShowModelCacheWarningIfNeeded = mock(async () => {})
@@ -42,6 +42,11 @@ mock.module("../../shared/logger", () => ({
 
 const { createAutoUpdateCheckerHook } = await import("./hook")
 
+afterEach(() => {
+  delete process.env.OPENCODE_CLI_RUN_MODE
+  mock.restore()
+})
+
 describe("createAutoUpdateCheckerHook", () => {
   it("skips startup toasts and checks in CLI run mode", async () => {
     //#given - CLI run mode enabled
@@ -78,6 +83,5 @@ describe("createAutoUpdateCheckerHook", () => {
     expect(mockShowVersionToast).not.toHaveBeenCalled()
     expect(mockRunBackgroundUpdateCheck).not.toHaveBeenCalled()
 
-    delete process.env.OPENCODE_CLI_RUN_MODE
   })
 })

src/hooks/auto-update-checker/hook/background-update-check.test.ts

@@ -40,7 +40,7 @@ mock.module("../../../shared/logger", () => ({
   log: () => {},
 }))
 
-const { runBackgroundUpdateCheck } = await import("./background-update-check")
+const { runBackgroundUpdateCheck } = await import("./background-update-check?test")
 
 describe("runBackgroundUpdateCheck", () => {
   const mockCtx = { directory: "/test" } as any