wolfsshd: fail a daemon that never listens

start_wolfsshd now records whether the daemon's listening line appeared
in the ten seconds it waits for it. Without one it kills the daemon and
clears PID, which puts the start through the empty-PID check every
caller already has, so the run stops and names the daemon.

- the pid reaches the run registry before that check, so a daemon that
  came up but never bound is still reaped by the runner's teardown

apps/wolfsshd/test/start_sshd.sh

@@ -165,26 +165,41 @@ EOF
     # sleep -- would be refused, and the daemon's log would show no connection
     # at all. Wait for the daemon's own listening line, matched on its pid so
     # that a previous daemon's line in this appended log cannot satisfy it.
+    LISTENING=0
     if [ -n "$PID" ]; then
         for i in $(seq 1 100); do
             if sudo grep -qF "[PID $PID]: [SSHD] Listening on port" \
                     ./log.txt 2>/dev/null; then
+                LISTENING=1
                 break
             fi
             sleep 0.1
         done
     fi
 
-    printf "SSHD running on PID $PID\n"
-
     # Record the daemon in the run's registry, if the runner set one up. Test
     # scripts run as children of run_all_sshd_tests.sh, so a variable cannot
     # carry their pids back; a file can, which is what lets the runner's exit
     # teardown be specific to this run instead of killing every wolfsshd on
-    # the machine.
+    # the machine. Registered before the check below so a daemon that came up
+    # but never listened is still reaped by the runner's teardown.
     if [ -n "$PID" ] && [ -n "$WOLFSSHD_TEST_PIDFILE" ]; then
         printf '%s\n' "$PID" >> "$WOLFSSHD_TEST_PIDFILE" 2>/dev/null || true
     fi
+
+    # Ten seconds and no listening line: report it here rather than return a
+    # pid the caller will trust. Falling through left the caller's empty-PID
+    # check satisfied and the test connecting to a daemon that never bound,
+    # so the run failed as a refused connection somewhere later instead of as
+    # a daemon that did not come up. Clearing PID puts it through the check
+    # every caller already has.
+    if [ -n "$PID" ] && [ "$LISTENING" -eq 0 ]; then
+        printf "wolfSSHd pid %s never logged a listening port\n" "$PID" >&2
+        sudo kill $PID 2>/dev/null || true
+        PID=""
+    fi
+
+    printf "SSHD running on PID $PID\n"
 }
 
 # closes down the sshd session started by start_wolfsshd, using $PID.