testsuite: harden ki58/ki62 tests for the fleet

Two of the integrated MC/DC-audit tests were environment-fragile:

- ki58: asserted the exact string '100% done percentfile', but %f expands to the
  transfer-relative path (with leading dirs) when the source is an absolute path,
  so the basename assumption failed.  Assert the literal-percent escape '100% done '
  plus the file name instead (still RED on a broken %%: it emits '100%% done').

- ki62: killed daemon.kill() -- the listener -- but rsyncd forks a child per
  connection, so the child sender kept streaming and the receiver hung.  Parse the
  transfer child's pid from the daemon log ('[pid] rsync on <mod>/') and kill that.
  killpg is not usable: the test daemon shares this test's process group.

Fixes are unchanged; only the test drivers.

testsuite/ki58-log-format-percent_test.py

@@ -33,10 +33,15 @@ p = subprocess.run(
 if p.returncode != 0:
     test_fail(f"rsync exited {p.returncode}:\n{p.stderr}")
 
-expected = '100% done percentfile'
-if expected not in p.stdout:
+# %f expands to the transfer-relative path, which includes leading directories
+# when the source is addressed by an absolute path (as here) -- so don't pin the
+# exact filename.  The point of this test is the escape: "100% done " with a
+# single literal percent followed by a space (a broken %% consumes the space or
+# leaves a doubled percent), plus the transferred file name somewhere.
+if '100% done ' not in p.stdout or 'percentfile' not in p.stdout:
     test_fail(
-        f"expected {expected!r} in --out-format output, got:\n{p.stdout}"
+        "expected '100% done ' (a single literal percent) and 'percentfile' in "
+        f"--out-format output, got:\n{p.stdout}"
     )
 
 print("ki58-log-format-percent: %% literal-percent escape verified")

testsuite/ki62-io-error-mask_test.py

@@ -19,12 +19,15 @@
 # Exit codes: 0 pass, 1 fail, 77 skip (killable daemon testing not possible --
 # the test needs --use-tcp so it can SIGKILL the sender process directly).
 
+import os
+import re
+import signal
 import subprocess
 import sys
 import time
 
 from rsyncfns import (
-    FROMDIR, TODIR, claim_ports, make_data_file, makepath, rmtree,
+    FROMDIR, SCRATCHDIR, TODIR, claim_ports, make_data_file, makepath, rmtree,
     rsync_argv, start_rsyncd, test_fail, test_skipped, build_rsyncd_conf,
     USE_TCP,
 )
@@ -97,7 +100,23 @@ client = subprocess.Popen(
 # (the path that exercises the io_error -> exit-code mapping).
 time.sleep(2)
 
-# Kill the sender (daemon) mid-transfer.
+# Kill the sender mid-transfer.  rsyncd forks a child per connection, so the
+# actual sender is NOT `daemon` (the listener) -- killing only the listener
+# leaves the child streaming and the receiver never sees EOF.  The child logs
+# "[pid] rsync on <module>/" to the daemon log; kill that pid (plus the
+# listener).  The daemon shares this test's process group, so killpg is not an
+# option (it would kill the test itself).
+child_pids = []
+try:
+    logtext = (SCRATCHDIR / 'rsyncd.log').read_text()
+    child_pids = [int(pid) for pid in re.findall(r'\[(\d+)\] rsync on ', logtext)]
+except OSError:
+    pass
+for pid in child_pids:
+    try:
+        os.kill(pid, signal.SIGKILL)
+    except (ProcessLookupError, PermissionError):
+        pass
 if daemon.poll() is None:
     daemon.kill()
     try: