refactor: multi-dashboard structural migration

- Rename dbt project from toronto_housing to portfolio
- Restructure dbt models into domain subdirectories:
  - shared/ for cross-domain dimensions (dim_time)
  - staging/toronto/, intermediate/toronto/, marts/toronto/
- Update SQLAlchemy models for raw_toronto schema
- Add explicit cross-schema FK relationships for FactRentals
- Namespace figure factories under figures/toronto/
- Namespace notebooks under notebooks/toronto/
- Update Makefile with domain-specific targets and env loading
- Update all documentation for multi-dashboard structure

This enables adding new dashboard projects (e.g., /football, /energy)
without structural conflicts or naming collisions.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

portfolio_app/figures/toronto/radar.py

@@ -0,0 +1,166 @@
+"""Radar/spider chart figure factory for multi-metric comparison."""
+
+from typing import Any
+
+import plotly.graph_objects as go
+
+
+def create_radar_figure(
+    data: list[dict[str, Any]],
+    metrics: list[str],
+    name_column: str | None = None,
+    title: str | None = None,
+    fill: bool = True,
+    colors: list[str] | None = None,
+) -> go.Figure:
+    """Create radar/spider chart for multi-axis comparison.
+
+    Each record in data represents one entity (e.g., a neighbourhood)
+    with values for each metric that will be plotted on a separate axis.
+
+    Args:
+        data: List of data records, each with values for the metrics.
+        metrics: List of metric column names to display on radar axes.
+        name_column: Column name for entity labels.
+        title: Optional chart title.
+        fill: Whether to fill the radar polygons.
+        colors: List of colors for each data series.
+
+    Returns:
+        Plotly Figure object.
+    """
+    if not data or not metrics:
+        return _create_empty_figure(title or "Radar Chart")
+
+    # Default colors
+    if colors is None:
+        colors = [
+            "#2196F3",
+            "#4CAF50",
+            "#FF9800",
+            "#E91E63",
+            "#9C27B0",
+            "#00BCD4",
+        ]
+
+    fig = go.Figure()
+
+    # Format axis labels
+    axis_labels = [m.replace("_", " ").title() for m in metrics]
+
+    for i, record in enumerate(data):
+        values = [record.get(m, 0) or 0 for m in metrics]
+        # Close the radar polygon
+        values_closed = values + [values[0]]
+        labels_closed = axis_labels + [axis_labels[0]]
+
+        name = (
+            record.get(name_column, f"Series {i + 1}")
+            if name_column
+            else f"Series {i + 1}"
+        )
+        color = colors[i % len(colors)]
+
+        fig.add_trace(
+            go.Scatterpolar(
+                r=values_closed,
+                theta=labels_closed,
+                name=name,
+                line={"color": color, "width": 2},
+                fill="toself" if fill else None,
+                fillcolor=f"rgba{_hex_to_rgba(color, 0.2)}" if fill else None,
+                hovertemplate="%{theta}: %{r:.1f}<extra></extra>",
+            )
+        )
+
+    fig.update_layout(
+        title=title,
+        polar={
+            "radialaxis": {
+                "visible": True,
+                "gridcolor": "rgba(128,128,128,0.3)",
+                "linecolor": "rgba(128,128,128,0.3)",
+                "tickfont": {"color": "#c9c9c9"},
+            },
+            "angularaxis": {
+                "gridcolor": "rgba(128,128,128,0.3)",
+                "linecolor": "rgba(128,128,128,0.3)",
+                "tickfont": {"color": "#c9c9c9"},
+            },
+            "bgcolor": "rgba(0,0,0,0)",
+        },
+        paper_bgcolor="rgba(0,0,0,0)",
+        font_color="#c9c9c9",
+        showlegend=len(data) > 1,
+        legend={"orientation": "h", "yanchor": "bottom", "y": -0.2},
+        margin={"l": 40, "r": 40, "t": 60, "b": 40},
+    )
+
+    return fig
+
+
+def create_comparison_radar(
+    selected_data: dict[str, Any],
+    average_data: dict[str, Any],
+    metrics: list[str],
+    selected_name: str = "Selected",
+    average_name: str = "City Average",
+    title: str | None = None,
+) -> go.Figure:
+    """Create radar chart comparing a selection to city average.
+
+    Args:
+        selected_data: Data for the selected entity.
+        average_data: Data for the city average.
+        metrics: List of metric column names.
+        selected_name: Label for selected entity.
+        average_name: Label for average.
+        title: Optional chart title.
+
+    Returns:
+        Plotly Figure object.
+    """
+    if not selected_data or not average_data:
+        return _create_empty_figure(title or "Comparison")
+
+    data = [
+        {**selected_data, "__name__": selected_name},
+        {**average_data, "__name__": average_name},
+    ]
+
+    return create_radar_figure(
+        data=data,
+        metrics=metrics,
+        name_column="__name__",
+        title=title,
+        colors=["#4CAF50", "#9E9E9E"],
+    )
+
+
+def _hex_to_rgba(hex_color: str, alpha: float) -> tuple[int, int, int, float]:
+    """Convert hex color to RGBA tuple."""
+    hex_color = hex_color.lstrip("#")
+    r = int(hex_color[0:2], 16)
+    g = int(hex_color[2:4], 16)
+    b = int(hex_color[4:6], 16)
+    return (r, g, b, alpha)
+
+
+def _create_empty_figure(title: str) -> go.Figure:
+    """Create an empty figure with a message."""
+    fig = go.Figure()
+    fig.add_annotation(
+        text="No data available",
+        xref="paper",
+        yref="paper",
+        x=0.5,
+        y=0.5,
+        showarrow=False,
+        font={"size": 14, "color": "#888888"},
+    )
+    fig.update_layout(
+        title=title,
+        paper_bgcolor="rgba(0,0,0,0)",
+        font_color="#c9c9c9",
+    )
+    return fig