Add basal/bolus/carb/target overlays to the Live and Dagoverzicht charts

Overlay the full insulin picture onto the interactive glucose charts:
basal rate as a semi-transparent step-area (profile schedule overridden
by active temp basal), bolus doses as size-scaled dots split into
food/correction/SMB categories (food and correction labeled with units,
SMB left unlabeled), carbs as bars, and the pump's target glucose as a
line — each with its own color, alpha, and legend entry. Shared trace-
building helpers live in ui_common.py so both pages (and the PDF report
in a follow-up PR) render identically.

Builds on the pump profile work in #29 (profile_data.py, load_profile()).

tests/test_ui_common.py

@@ -1,8 +1,13 @@
+import pandas as pd
 import plotly.graph_objects as go
 
 from ui_common import (
     PALETTE,
     THRESHOLD_LINES,
+    add_basal_area_trace,
+    add_bolus_marker_traces,
+    add_carb_bars_trace,
+    add_target_line_trace,
     add_threshold_lines,
     build_tir_stacked_bar_figure,
     hex_to_rgba,
@@ -36,3 +41,99 @@ def test_build_tir_stacked_bar_figure_has_one_bar_trace_per_band():
     assert len(fig.data) == 5
     assert [trace.y[0] for trace in fig.data] == [1.0, 3.0, 80.0, 12.0, 4.0]
     assert fig.layout.barmode == "stack"
+
+
+def test_add_basal_area_trace_adds_one_filled_step_trace():
+    basal = pd.DataFrame(
+        {"timestamp": pd.to_datetime(["2026-01-01 00:00", "2026-01-01 06:00"]), "rate": [0.8, 1.2]}
+    )
+    fig = go.Figure()
+    add_basal_area_trace(fig, basal, PALETTE["light"])
+    assert len(fig.data) == 1
+    assert fig.data[0].name == "Basaal"
+    assert fig.data[0].fill == "tozeroy"
+    assert fig.data[0].line.shape == "hv"
+
+
+def test_add_basal_area_trace_skips_empty_input():
+    fig = go.Figure()
+    add_basal_area_trace(fig, pd.DataFrame(columns=["timestamp", "rate"]), PALETTE["light"])
+    assert len(fig.data) == 0
+
+
+def test_add_carb_bars_trace_adds_one_bar_trace():
+    carbs = pd.DataFrame({"timestamp": pd.to_datetime(["2026-01-01 08:00"]), "carbs": [40.0]})
+    fig = go.Figure()
+    add_carb_bars_trace(fig, carbs, PALETTE["light"])
+    assert len(fig.data) == 1
+    assert fig.data[0].name == "Koolhydraten"
+    assert isinstance(fig.data[0], go.Bar)
+
+
+def test_add_bolus_marker_traces_adds_one_trace_per_category_present():
+    bolus = pd.DataFrame(
+        {
+            "timestamp": pd.to_datetime(["2026-01-01 08:00", "2026-01-01 12:00"]),
+            "insulin": [4.0, 0.3],
+            "category": ["food", "smb"],
+        }
+    )
+    fig = go.Figure()
+    add_bolus_marker_traces(fig, bolus, PALETTE["light"], lane_y=2.0)
+    names = {trace.name for trace in fig.data}
+    assert names == {"Bolus (voeding)", "SMB"}
+
+
+def test_add_bolus_marker_traces_labels_food_and_correction_but_not_smb():
+    bolus = pd.DataFrame(
+        {
+            "timestamp": pd.to_datetime(["2026-01-01 08:00", "2026-01-01 12:00"]),
+            "insulin": [4.0, 0.3],
+            "category": ["food", "smb"],
+        }
+    )
+    fig = go.Figure()
+    add_bolus_marker_traces(fig, bolus, PALETTE["light"], lane_y=2.0)
+    by_name = {trace.name: trace for trace in fig.data}
+    assert by_name["Bolus (voeding)"].mode == "markers+text"
+    assert by_name["SMB"].mode == "markers"
+
+
+def test_add_bolus_marker_traces_skips_empty_input():
+    fig = go.Figure()
+    add_bolus_marker_traces(fig, pd.DataFrame(columns=["timestamp", "insulin", "category"]), PALETTE["light"], 2.0)
+    assert len(fig.data) == 0
+
+
+def test_add_target_line_trace_adds_one_line_trace():
+    target = pd.DataFrame({"timestamp": pd.to_datetime(["2026-01-01 00:00"]), "target": [6.5]})
+    fig = go.Figure()
+    add_target_line_trace(fig, target, PALETTE["light"])
+    assert len(fig.data) == 1
+    assert fig.data[0].name == "Streefwaarde (pomp)"
+
+
+def test_add_target_line_trace_skips_empty_input():
+    fig = go.Figure()
+    add_target_line_trace(fig, pd.DataFrame(columns=["timestamp", "target"]), PALETTE["light"])
+    assert len(fig.data) == 0
+
+
+def test_overlay_traces_support_an_hour_based_x_column_for_dagoverzicht():
+    """Dagoverzicht plot elke dag op een gedeelde 0-24u-as ('hour') i.p.v. echte
+    datums; de hover mag daar dan ook geen datumformattering tonen."""
+    basal = pd.DataFrame({"hour": [0.0, 6.0], "rate": [0.8, 1.2]})
+    carbs = pd.DataFrame({"hour": [8.0], "carbs": [40.0]})
+    bolus = pd.DataFrame({"hour": [8.0], "insulin": [4.0], "category": ["food"]})
+    target = pd.DataFrame({"hour": [0.0], "target": [6.5]})
+
+    fig = go.Figure()
+    add_basal_area_trace(fig, basal, PALETTE["light"], x_col="hour")
+    add_carb_bars_trace(fig, carbs, PALETTE["light"], x_col="hour")
+    add_bolus_marker_traces(fig, bolus, PALETTE["light"], lane_y=2.0, x_col="hour")
+    add_target_line_trace(fig, target, PALETTE["light"], x_col="hour")
+
+    assert len(fig.data) == 4
+    bolus_trace = next(t for t in fig.data if t.name == "Bolus (voeding)")
+    assert list(bolus_trace.x) == [8.0]
+    assert "%d-%m" not in bolus_trace.hovertemplate