test(plugins): make the refresh spinner hold deterministic

Extract settleRefresh() so the spinner-minimum hold has one settle point,
advance the e2e fake clock past the 400ms hold before asserting the button
restores, and drive the disposal-during-hold store test on fake timers for
both success and failure reads.

apps/web/tests/plugin-manager.e2e.ts

@@ -312,6 +312,7 @@ describe('web e2e: plugin manager', () => {
             await recordRefresh(`${outcome}: pending`)
 
             release.resolve(undefined)
+            await probe.clock.runFor(400)
             await expect.poll(() => refresh.isEnabled()).toBe(true)
             expect(await refresh.getAttribute('aria-busy')).toBe('false')
             expect(await panel.getAttribute('aria-busy')).toBe('false')

packages/client/ui-plugin-manager/src/client/manager-store.ts

@@ -744,15 +744,19 @@ export class PluginManagerController {
       // Hold the spinner to its minimum so a fast read does not flash it, then settle.
       const remaining = REFRESH_SPINNER_MIN_MS - (Date.now() - startedAt)
       if (remaining > 0) await new Promise<void>((resolve) => { setTimeout(resolve, remaining) })
-      if (!this.disposed) {
-        const failed = this.getSnapshot().status === 'error'
-        this.patch(failed && this.hasCachedInventory
-          ? { status: 'ready', refreshStatus: 'idle', notice: { kind: 'refresh-failed', seq: ++this.noticeSeq } }
-          : { refreshStatus: failed ? 'failed' : 'idle' })
-      }
+      this.settleRefresh()
     }
   }
 
+  /** Publish refresh feedback only before disposal. */
+  private settleRefresh(): void {
+    if (this.disposed) return
+    const failed = this.getSnapshot().status === 'error'
+    this.patch(failed && this.hasCachedInventory
+      ? { status: 'ready', refreshStatus: 'idle', notice: { kind: 'refresh-failed', seq: ++this.noticeSeq } }
+      : { refreshStatus: failed ? 'failed' : 'idle' })
+  }
+
   private async read(): Promise<void> {
     try {
       do {

packages/client/ui-plugin-manager/tests/manager-store.client.spec.ts

@@ -1233,18 +1233,28 @@ describe('PluginManagerController', () => {
     expect(state()).toBe(before)
   })
 
-  it('drops a manual refresh that settles after disposal', async () => {
-    const gate = deferred<ReturnType<typeof ok<BundleInfo[]>>>()
-    const { plugins, face, state, controller } = bench()
-    await controller.load()
-    plugins.listBundles.mockReturnValueOnce(gate.promise)
-    face.refresh()
-    await vi.waitFor(() => { expect(state().refreshStatus).toBe('refreshing') })
-    controller.dispose()
-    const before = state()
-    gate.resolve(ok([{ ...BUNDLE, version: '9.9.9' }]))
-    await new Promise<void>((resolve) => { setTimeout(resolve, 10) })
-    expect(state()).toBe(before)
+  it.each([false, true])('drops refresh feedback when disposed during the spinner hold (failure: %s)', async (failure) => {
+    vi.useFakeTimers()
+    try {
+      const { plugins, face, state, controller } = bench()
+      await controller.load()
+      plugins.listBundles.mockResolvedValueOnce(failure ? refused('gateway/internal', 'offline') : ok([BUNDLE]))
+      face.refresh()
+      await vi.advanceTimersByTimeAsync(0)
+      expect(state().refreshStatus).toBe('refreshing')
+      expect(vi.getTimerCount()).toBe(1)
+      const before = state()
+      const listener = vi.fn()
+      const unsubscribe = face.hooks.pluginManager.subscribe(listener)
+      onTestFinished(unsubscribe)
+      controller.dispose()
+      await vi.advanceTimersByTimeAsync(400)
+      expect(state()).toBe(before)
+      expect(listener).not.toHaveBeenCalled()
+      expect(vi.getTimerCount()).toBe(0)
+    } finally {
+      vi.useRealTimers()
+    }
   })
 
   it('settles a manual refresh whose read outlasts the spinner minimum without an extra hold', async () => {