feat(widgets): a troubled container on the Docker widget says since when (#5810)

Its problems and since come from the same container_problems and
problem_since the Docker page uses, read from the day's deaths and
health changes; troubled containers sort worst problem first, then name.

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

tests/plugins/docker/test_docker_page.py

@@ -299,6 +299,16 @@ async def test_the_services_widget_lists_what_is_wrong_then_packs_the_healthy(ap
     assert not hex_colours(page), hex_colours(page)
 
 
+async def test_a_troubled_container_says_since_when_on_the_widget(app):
+    """#5810: a container in trouble carries its since, as the Docker page does."""
+    sick = _c("backup_cron", host_id="h1", status="running", health="unhealthy")
+    page = await _services_widget(
+        app, bad_containers=[sick],
+        bad_since={("h1", "backup_cron"): datetime.now(timezone.utc) - timedelta(minutes=40)})
+    page = " ".join(page.split())
+    assert "unhealthy since <time" in page and "40m ago" in page and "· VDNT-Docker02" in page
+
+
 async def test_the_services_widget_says_when_all_is_well(app):
     page = await _services_widget(app, services_total=2, services_healthy=2, running_count=1,
                                   healthy=[{"kind": "service", "s": _widget_svc("a")}])