Fetch Gmail messages ten to a request, not a minute's worth in a second

On a project allowed 6,000 units a minute an import fetched one batch,
was refused, waited a minute and was refused on the next batch: the
indicator read "paused" beside "about 1,005 of 6,000 units". Fifty
messages in one batch request are 1,000 units in one second, and Google
does not let a per-minute limit be spent that way (#90).

  requests     ten messages each, the pacer asked before every one;
               a refused request stops the rest of its batch, which is
               handed back unfetched
  the reserve  five seconds of allowance instead of twenty, so the
               pacer no longer lets a burst through that Google will
               refuse
  the line     while paused it shows what had been counted when Google
               refused, not a running count that has fallen to nothing

That a burst is what Google refused is inferred from the figures, not
documented.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

templates/mail/_jobs_indicator.html.twig

@@ -165,7 +165,7 @@ the record and a missed nudge costs one stale render, never a wrong answer.
                                    the limit is only assumed is the end of the
                                    sentence, and the part that was cut off. #}
                                 <p class="mt-0.5 text-[11px] text-ink-faint" data-import-quota>
-                                    {{ (line.quota.learnt ? 'jobs.import.quota' : 'jobs.import.quota_assumed')|trans({
+                                    {{ (line.quota.isPaused() ? 'jobs.import.quota_refused' : (line.quota.learnt ? 'jobs.import.quota' : 'jobs.import.quota_assumed'))|trans({
                                         '%used%': line.quota.used|number_format,
                                         '%limit%': line.quota.limit|number_format,
                                     }) }}