fix: remove shot special-case; treat simulate.close as abort per maintainer guidance

Per feedback on #4579: a premature socket close (simulate.close or a real
TCP disconnect on Node.js v24+) is correctly treated as a client abort.
Remove the req._shot guard that was suppressing abort detection for shot
inject requests and update the test to expect 499 instead of 500.

The false branch of the final condition is structurally unreachable — after
all early returns, only 'abort' and 'close' events reach that point — so a
$lab:coverage:off$ annotation is used for the one unavoidable uncovered branch.

Author: sapirbaruch

lib/request.js

@@ -747,12 +747,13 @@ internals.event = function ({ request }, event, err) {
 
     request._eventContext.request = null;
 
-    // On Node.js v24+, 'aborted' was removed.  A 'close' on the response before writableEnded
-    // means the client disconnected mid-request — treat it as an abort.  We exclude @hapi/shot
-    // inject requests (identified by req._shot) because shot fires req.emit('close') for its
-    // simulate.close scenario but that should not be treated as a client abort.
-    if (event === 'abort' ||
-        (event === 'close' && !request.raw.res.writableEnded && !request.raw.req._shot)) {
+    // Treat as abort when: (a) the IncomingMessage fired 'aborted' (Node.js < v24), or (b) the
+    // response closed before writableEnded (guaranteed above) — the Node.js v24+ signal.
+    // The false branch is structurally unreachable: after all early returns above, only 'abort'
+    // and 'close' (with !writableEnded) events reach this point, so the condition is always true.
+    // $lab:coverage:off$
+    if (event === 'abort' || event === 'close') {
+        // $lab:coverage:on$
 
         // Calling _reply() means that the abort is applied immediately, unless the response has already
         // called _reply(), in which case this call is ignored and the transmit logic is responsible for

test/payload.js

@@ -76,7 +76,7 @@ describe('Payload', () => {
         server.inject({ method: 'POST', url: '/', payload: 'test', simulate: { close: true, end: false } });
         const request = await responded;
         expect(request._isReplied).to.equal(true);
-        expect(request.response.output.statusCode).to.equal(500);
+        expect(request.response.output.statusCode).to.equal(499);
     });
 
     it('handles aborted request mid-lifecycle step', async (flags) => {