feat(ui): audit, alert rules and the rule form say things in words (#5212)

#5212 "Plain labels: no raw ids, scopes, metric keys or unexplained jargon",
batch 1:

- Audit log: each action reads as a sentence ("paused monitor"), with the
  code as its tooltip. Detail shows flags as yes/no, lists joined, a run's
  scope by name, spans as spans, and no ids the entity column already gives.
  The filter is now a picker of areas.
- Alert rules, history and Status say the condition in words: "is down",
  "Fullest disk >= 85%". Readings use metric_value, and history times use
  |ago.
- Rule form: sources and metrics by name, the threshold's unit, "fires
  when it is down/up" for an up/down metric instead of 0.5, and a metric
  reference built from the catalog.
- Schedules and Maintenance: viewers no longer see Run now, Pause, Edit,
  Delete or New. Intervals and next runs read as "every 2h" and "in 3h";
  a scope reads "Every alert on Host agent".

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

tests/core/test_status_page.py

@@ -55,7 +55,7 @@ async def test_the_problems_come_first_and_say_since_when(app):
     problem_card = page[attention:page.index("</section>")]
     assert "shop-api" in problem_card and "nas" not in problem_card
     assert "down since <time" in problem_card and ">12m ago</time>" in problem_card
-    assert "CPU high" in problem_card and "cpu_pct &gt; 90" in problem_card and ">4m ago</time>" in problem_card
+    assert "CPU high" in problem_card and "web01 CPU &gt; 90%" in problem_card and ">4m ago</time>" in problem_card
     assert '<span class="badge badge-crit">Firing</span>' in problem_card
     # Uptime and TLS coloured by Settings → Thresholds, not by literals.
     assert '<span class="tone-crit">93.00%</span>' in page and '<span class="tone-ok">100.00%</span>' in page