test(subagent-acp): skip half-close cases on Windows

packages/subagent/subagent-acp/tests/subagent-acp.spec.ts

@@ -589,7 +589,10 @@ describe('dsh-subagent-acp', () => {
     )
   })
 
-  it('reports initialize-stage transport when the child closes the protocol but stays alive', async () => {
+  it.skipIf(
+    process.platform === 'win32',
+    'Windows anonymous pipes do not surface a child stdout half-close while the child stays alive',
+  )('reports initialize-stage transport when the child closes the protocol but stays alive', async () => {
     const error = await startAcpRun(request(), {
       command: process.execPath,
       args: [mockServer],
@@ -936,7 +939,10 @@ describe('dsh-subagent-acp', () => {
     await run.dispose()
   })
 
-  it('classifies a prompt transport failure without copying SDK text', async () => {
+  it.skipIf(
+    process.platform === 'win32',
+    'Windows anonymous pipes do not surface a child stdout half-close while the child stays alive',
+  )('classifies a prompt transport failure without copying SDK text', async () => {
     const run = await startAcpRun(request('private prompt text'), {
       command: process.execPath,
       args: [mockServer],
@@ -957,7 +963,10 @@ describe('dsh-subagent-acp', () => {
     await run.dispose()
   })
 
-  it('lets local cancellation interrupt prompt-failure process observation', async () => {
+  it.skipIf(
+    process.platform === 'win32',
+    'Windows anonymous pipes do not surface a child stdout half-close while the child stays alive',
+  )('lets local cancellation interrupt prompt-failure process observation', async () => {
     const controller = new AbortController()
     const protocolEnded = Promise.withResolvers<undefined>()
     let boundedExitWaits = 0