Dashboard: Stadium Night design system, 5-page Streamlit app, warehouse exporter

- src/export/warehouse.py: reads scattered pipeline artifacts → 6 Parquet files
  (players, fixtures, predictions, lineups, votes, model_metrics)
- dashboard/warehouse.py: read-only cached Parquet loader
- .streamlit/config.toml: dark theme base, server config
- dashboard/viz/template.py: Plotly 'fantabeto_dark' template (single source of truth)
  - Semantic palette: pitch_green #00D084, gold #FFC94D, red #FF4D5E, sky #38BDF8
  - Space Grotesk headers, Inter body, tabular numerals
  - All 10 chart colors banned from default palette
- dashboard/viz/components.py: KPI cards, role chips, section headers, CSS injection
- dashboard/viz/charts.py: 10 pure chart functions (df → Figure)
  - percentile radar, fixture heatmap, regression comparison, bonus donut
  - card risk gauge, budget waterfall, value scatter, error violins
- dashboard/viz/pitch.py: SVG pitch component — dark turf gradient,
  player badges sized by FV, gold captain ring, bench strip, formation label
- 5 pages:
  - 01_matchday: KPI sparklines, fixture heatmap, start/sit grid, bump chart
  - 02_players: search, radar, regression, bonus/malus, card risk, news feed
  - 03_auction: budget slider, waterfall, value scatter, grid auction heatmap
  - 04_lineup: SVG pitch, what-if toggles, opponent mirror, MCTS captain
  - 05_lab: error violins, feature importance, calibration curve, backtest
- dashboard/app.py: multi-page Streamlit entry with sidebar navigation
- dashboard/tests/test_dashboard.py: 18 unit tests (warehouse, template, charts, pitch)
- DASHBOARD.md: full architecture docs, design system reference
- 49 total tests passing (31 existing + 18 dashboard)

dashboard/viz/components.py

@@ -0,0 +1,101 @@
+"""Reusable UI components: KPI cards, role chips, insight row, section headers."""
+
+import streamlit as st
+from .template import (
+    PITCH_GREEN, GOLD, RED, SKY, VIOLET, WHITE, TEXT_SECONDARY,
+    CARD_BG, BORDER, ROLE_COLORS, ROLE_ICONS,
+)
+
+CSS_CLASS = """
+<style>
+@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@500;700&family=Inter:wght@400;500;600&display=swap');
+
+.kpi-card {
+    background: rgba(17, 24, 39, 0.70);
+    backdrop-filter: blur(8px);
+    border: 1px solid #1F2937;
+    border-radius: 14px;
+    padding: 18px 20px;
+    text-align: center;
+    transition: border-color 0.2s;
+}
+.kpi-card:hover { border-color: #374151; }
+.kpi-value {
+    font-family: 'Space Grotesk', sans-serif;
+    font-size: 28px;
+    font-weight: 700;
+    letter-spacing: -0.5px;
+}
+.kpi-label {
+    font-family: 'Inter', sans-serif;
+    font-size: 11px;
+    color: #9CA3AF;
+    text-transform: uppercase;
+    letter-spacing: 0.8px;
+    margin-top: 4px;
+}
+.kpi-sub {
+    font-family: 'Inter', sans-serif;
+    font-size: 12px;
+    margin-top: 2px;
+}
+.role-chip {
+    display: inline-block;
+    font-family: 'Inter', sans-serif;
+    font-size: 10px;
+    font-weight: 600;
+    padding: 2px 8px;
+    border-radius: 4px;
+    margin-right: 4px;
+}
+.section-header {
+    font-family: 'Space Grotesk', sans-serif;
+    font-size: 18px;
+    font-weight: 600;
+    color: #E5E7EB;
+    margin-bottom: 0;
+}
+.insight {
+    font-family: 'Inter', sans-serif;
+    font-size: 12px;
+    color: #9CA3AF;
+    font-style: italic;
+    margin-top: 2px;
+}
+</style>
+"""
+
+
+def inject_css():
+    st.markdown(CSS_CLASS, unsafe_allow_html=True)
+
+
+def kpi_card(label: str, value: str, sub: str = "", color: str = WHITE, delta: float | None = None):
+    delta_html = ""
+    if delta is not None:
+        d_color = PITCH_GREEN if delta >= 0 else RED
+        d_sign = "+" if delta > 0 else ""
+        delta_html = f'<span style="color:{d_color};font-size:13px;">{d_sign}{delta:+.1f}</span>'
+
+    return f"""
+    <div class="kpi-card">
+        <div class="kpi-value" style="color:{color};">{value}{delta_html}</div>
+        <div class="kpi-label">{label}</div>
+        {f'<div class="kpi-sub">{sub}</div>' if sub else ''}
+    </div>
+    """
+
+
+def role_chip(role: str) -> str:
+    color = ROLE_COLORS.get(role, TEXT_SECONDARY)
+    return f'<span class="role-chip" style="background:{color}22;color:{color};border:1px solid {color}44;">{ROLE_ICONS.get(role, "")} {role}</span>'
+
+
+def section(title: str, caption: str = ""):
+    st.markdown(f'<p class="section-header">{title}</p>', unsafe_allow_html=True)
+    if caption:
+        st.markdown(f'<p class="insight">{caption}</p>', unsafe_allow_html=True)
+
+
+def insight(text: str):
+    st.markdown(f'<p class="insight">{text}</p>', unsafe_allow_html=True)