feat(docker): Busiest Containers shows bars of the last hours beside each figure, scaled to the row's peak with a floor (#5214)

The fill bars were a share of the host's capacity, a sliver on hosts with
80 cores. Each figure now sits beside 24 bars of the last 6 hours (1h/24h
per widget), each row scaled to its own peak but never below 1 core or
1 GiB (configurable per widget), so a 0.05-core container reads flat and
a bar's height means real load. One grouped date_bin query feeds them.

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

tests/plugins/docker/test_docker_page.py

@@ -218,23 +218,52 @@ def test_a_container_reads_by_its_service_or_ci_job():
     assert svc.display_name(_c("portainer_agent")) == "portainer_agent"
 
 
-async def test_busiest_containers_show_the_number_with_its_scale(app):
-    """#5253: every bar has its figure; the widget names the busiest."""
+def _bars(values, floor):
+    return svc.scaled_bars(values, floor)
+
+
+async def test_busiest_containers_show_the_number_beside_its_recent_bars(app):
+    """#5253, #5214: every figure has its unit; the bars beside it are the last
+    hours, scaled to the row's own peak; the widget names the busiest."""
     rows = [
         {"c": _c("GITEA-ACTIONS-TASK-1-WORKFLOW-Android-JOB-build-0123456789abcdef0"),
          "label": "CI: Android · build", "host_name": "VDNT-Docker03",
          "usage": {"cores": 1.62, "cpus": 8, "cpu_share": 20.25, "mem_bytes": 820 * 2**20,
-                   "mem_pct": 5.0, "mem_of": "the host's memory", "mem_limit": None}},
+                   "mem_pct": 5.0, "mem_of": "the host's memory", "mem_limit": None},
+         "cpu_bars": _bars([None, 0.8, 3.2, 1.6], 1.0), "mem_bars": _bars([None] * 4, 2**30)},
         {"c": _c("tdarr"), "label": "tdarr", "host_name": "VDNT-Docker03",
          "usage": {"cores": 0.25, "cpus": 8, "cpu_share": 3.1, "mem_bytes": None,
-                   "mem_pct": None, "mem_of": None, "mem_limit": None}},
+                   "mem_pct": None, "mem_of": None, "mem_limit": None},
+         "cpu_bars": _bars([0.25] * 4, 1.0), "mem_bars": _bars([None] * 4, 2**30)},
     ]
     async with app.test_request_context("/plugins/docker/widget/resources"):
         page = await render_plugin_template(app, "docker", "docker/widget_resources.html",
-                                            rows=rows, minutes=5, widget_id="1")
+                                            rows=rows, minutes=5, hours=6, cpu_floor=1.0,
+                                            mem_floor=2**30, widget_id="1")
     assert "Busiest: <strong>CI: Android · build</strong> on VDNT-Docker03" in page and "1.6 of 8 cores" in page
-    assert ">1.6 cores<" in page and ">0.25 cores<" in page and ">820.0 MiB<" in page
-    assert "--pct:20.25%" in page and ">—<" in page
+    assert ">1.6 cores<" in page and ">0.25 cores<" in page and ">820.0 MiB<" in page and ">—<" in page
+    # Android peaks at 3.2 cores, so 1.6 is half height; tdarr's 0.25 sits under the 1-core floor.
+    assert 'class="gap"' in page and "height:50.0%" in page and "height:25.0%" in page
+    assert "Peak 3.2 cores in the last 6h; bars reach the top at 3.2 cores" in page
+    assert "Peak 0.25 cores in the last 6h; bars reach the top at 1.0 cores" in page
+    assert "No samples in the last 6h" in page
     assert len(re.findall(r"<th[ >]", page)) == 4
     assert ">CI: Android · build<" in page        # the long CI name only as the hover title
     assert not hex_colours(page), hex_colours(page)
+
+
+def test_bars_reach_the_peak_but_never_below_the_floor():
+    """#5214: a 0.05 → 0.10 wobble stays near the floor; a 1.5 → 3 spike fills."""
+    idle = svc.scaled_bars([0.05, 0.10, None], 1.0)
+    assert idle == {"bars": [5.0, 10.0, None], "peak": 0.10, "roof": 1.0}
+    busy = svc.scaled_bars([1.5, 3.0], 1.0)
+    assert busy["bars"] == [50.0, 100.0] and busy["roof"] == 3.0
+    assert svc.scaled_bars([None, None], 1.0) == {"bars": [None, None], "peak": None, "roof": 1.0}
+
+
+def test_bar_slots_end_at_the_bucket_now_falls_in():
+    now = datetime(2026, 10, 7, 12, 7, 30, tzinfo=timezone.utc)
+    slots, width = svc.bar_slots(now, 6)
+    assert width == 900 and len(slots) == 24
+    assert slots[-1] == datetime(2026, 10, 7, 12, 0, tzinfo=timezone.utc)
+    assert slots[0] == datetime(2026, 10, 7, 6, 15, tzinfo=timezone.utc)