Merge 0.12->trunk

util.startup: Fix async waiting for last shutdown steps Observed problem: When shutting down prosody would immediately exit after waiting for s2s connections to close, skipping the last cleanup events and reporting the exit reason and code. This happens because prosody.main_thread is in a waiting state and queuing startup.shutdown is dispatched trough the main loop via nexttick, but since the main loop was no longer running at that point it proceeded to the end of the prosody script and exited there.

mod_csi_simple: Collect stats on number of stanzas per flush Because interesting, gives some idea about the efficiency.

mod_admin_shell: Show session id ping reply came To point out which one when more than one connection was established, or if it's an existing connection, allows correlation with s2s:show() or with logs.

Merge 0.12->trunk

mod_smacks: Fix #1761 by setting a flag earlier This ensures that the flag is set even if the pre-drain callback is called from send(), as would be the case if opportunistic writes are enabled.

net.http.codes: Refresh from registry, many refs now point to RFC9110

util.watchdog: Allow passing a new timeout to :reset()

util.watchdog: Allow :reset() to restart a cancelled watchdog

util.watchdog: Update to use "new" util.timer API When this module was written, it wasn't possible to cancel or reschedule a timer. Times have changed, and we should take advantage of those new methods. This module becomes a very thin wrapper around util.timer now, but I'd argue it's still a very common and useful concept/abstraction to have around. Possible API change: this removes the 'last_reset' field of the watchdog. This was never really intended as a public thing, and I can't find any code that uses it, so I consider removal to be safe.