fix(bug-1560): symlink-escape test asserted the wrong error string

test_recordstart_symlink_escape_replies_error expected "invalid record
file name" (the -EINVAL string), but sched_validate_record_filename()'s
canonical-path containment check has always, correctly, returned
-EACCES ("permission denied accessing record file") for a symlink
escaping record_dir -- confirmed against test_recording_path_validation.c's
own direct unit test for the identical scenario, which already asserts
-EACCES and has always passed.

Not environment-dependent as originally suspected (this project's
buglog carried it as a uid-1000-vs-root permission-check-ordering
theory across 7+ sightings since Aug 15) -- it fails identically
regardless of uid, since escape-containment and filesystem-permission
errors were never actually conflated in production code, only in this
test's assertion. No production code changed.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019QxaSzHRB7pmYFp4cVnwkA

src/scheduler/testsuite/test_admin_request.c

@@ -826,7 +826,25 @@ static void test_recordstart_symlink_escape_replies_error(void)
      * '/' nor the ".." rule -- only the canonical-path containment check
      * on the pre-existing symlink's resolved target catches this. Proven
      * here through the real admin request path, not just at the internal
-     * sched_validate_record_filename() level. */
+     * sched_validate_record_filename() level.
+     *
+     * bug-1560: a canonical-path containment failure is deliberately
+     * -EACCES, not -EINVAL (sched_validate_record_filename(),
+     * recording.c's path_is_contained() branch) -- -EINVAL is reserved
+     * for a malformed filename rejected before any filesystem access
+     * (Step 1: '/' or ".." in the bare filename, see
+     * test_recordstart_dotdot_filename_replies_error above). The sibling
+     * unit test at the sched_validate_record_filename() level already
+     * asserts -EACCES for this exact scenario
+     * (test_symlink_inside_record_dir_escaping_outside_is_rejected,
+     * test_recording_path_validation.c) -- this test's own expected
+     * error string below was simply wrong, asserting the -EINVAL string
+     * against what is, and always was, an -EACCES rejection. Not an
+     * environment-dependent permission-check ordering issue as
+     * originally suspected: this fails identically as uid 0 or uid
+     * 1000, since escape-containment and filesystem-permission errors
+     * were never actually conflated in production code -- only in this
+     * test's assertion. */
     snprintf(outside_target, sizeof(outside_target), "%s/secret", outside_dir);
     touch_file(outside_target);
 
@@ -847,7 +865,8 @@ static void test_recordstart_symlink_escape_replies_error(void)
     TEST_ASSERT_EQUAL_INT(1, g_reply_calls);
     TEST_ASSERT_FALSE(g_last_ok);
     TEST_ASSERT_FALSE(g_last_error_null);
-    TEST_ASSERT_EQUAL_STRING("invalid record file name", g_last_error);
+    TEST_ASSERT_EQUAL_STRING("permission denied accessing record file",
+                             g_last_error);
     TEST_ASSERT_FALSE(g_last_recording);
     TEST_ASSERT_TRUE(g_last_file_null);
     TEST_ASSERT_EQUAL_UINT64(0, g_last_event_count);