fix: normalize authorization stream creation errors

Author: vitry

scripts/zcode-companion.mjs

@@ -257,7 +257,9 @@ export function readInternalEnvelope(fd = 3, options = {}) {
   if (!Number.isSafeInteger(fd) || fd < 3 || !Number.isSafeInteger(maxBytes) || maxBytes <= 0 || !Number.isSafeInteger(timeoutMs) || timeoutMs <= 0) throw authorizationInputError();
   options.signal?.throwIfAborted();
   return new Promise((resolvePromise, reject) => {
-    const stream = options.createStream?.(fd) ?? new Socket({ fd, readable: true, writable: false });
+    let stream;
+    try { stream = options.createStream?.(fd) ?? new Socket({ fd, readable: true, writable: false }); }
+    catch { reject(authorizationInputError()); return; }
     let data = ''; let bytes = 0; let settled = false; let closed = false; let cleaned = false;
     /** @type {{resolve:true,value:any}|{resolve:false,value:unknown}|null} */
     let outcome = null;

tests/recovery.test.mjs

@@ -388,6 +388,15 @@ test('internal envelope closes its owned stream once on success, error, and time
   }
 });
 
+test('internal envelope maps synchronous stream construction failures to its stable error', async () => {
+  await assert.rejects(
+    readInternalEnvelope(33, { createStream: () => { throw new TypeError('secret unsupported descriptor'); } }),
+    (error) => error instanceof PluginError
+      && error.code === 'INTERNAL_AUTHORIZATION_INVALID'
+      && !error.message.includes('secret'),
+  );
+});
+
 test('internal response writer times out without blocking the event loop and closes once', async () => {
   let closes = 0; let ticked = false; setImmediate(() => { ticked = true; });
   await assert.rejects(writeInternalResponse({ ok: true }, 44, { timeoutMs: 10, write: () => {}, close: (_fd, callback) => { closes += 1; callback(); } }), { code: 'INTERNAL_RESPONSE_WRITE_TIMEOUT' });