fix(subagent-acp): correct it.skipIf call arity

it.skipIf takes only the condition; passing a reason string as a second
argument breaks tsc and fails every build. Move the explanation to a comment.

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

@@ -589,10 +589,9 @@ describe('dsh-subagent-acp', () => {
     )
   })
 
-  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 () => {
+  // Windows anonymous pipes do not surface a child stdout half-close while
+  // the child stays alive.
+  it.skipIf(process.platform === 'win32')('reports initialize-stage transport when the child closes the protocol but stays alive', async () => {
     const error = await startAcpRun(request(), {
       command: process.execPath,
       args: [mockServer],
@@ -939,10 +938,9 @@ describe('dsh-subagent-acp', () => {
     await run.dispose()
   })
 
-  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 () => {
+  // Windows anonymous pipes do not surface a child stdout half-close while
+  // the child stays alive.
+  it.skipIf(process.platform === 'win32')('classifies a prompt transport failure without copying SDK text', async () => {
     const run = await startAcpRun(request('private prompt text'), {
       command: process.execPath,
       args: [mockServer],
@@ -963,10 +961,9 @@ describe('dsh-subagent-acp', () => {
     await run.dispose()
   })
 
-  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 () => {
+  // Windows anonymous pipes do not surface a child stdout half-close while
+  // the child stays alive.
+  it.skipIf(process.platform === 'win32')('lets local cancellation interrupt prompt-failure process observation', async () => {
     const controller = new AbortController()
     const protocolEnded = Promise.withResolvers<undefined>()
     let boundedExitWaits = 0