fix(analytics): 4 UX polish fixes — resolution time column, empty states, type badges, select styling

- CoverageHeatmap: add Avg Resolution column with inverse color thresholds (green <10 min, amber 10–20 min, red >20 min); updated colSpan to 7
- FlowPilotAnalyticsPage: show positive empty state when knowledge gaps list is empty instead of rendering nothing
- FlowQualityTable: add tree_type badge next to flow name (Troubleshooting/Project/Maintenance with distinct colors)
- FlowPilotAnalyticsPage: add [&>option] Tailwind classes to period select for improved dark-theme contrast in Chrome/Firefox

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/components/analytics/CoverageHeatmap.tsx

@@ -85,6 +85,10 @@ export default function CoverageHeatmap({ data }: CoverageHeatmapProps) {
               <th className="px-3 py-2 text-right font-label text-[0.625rem] uppercase tracking-[0.1em] text-muted-foreground">
                 Guided %
               </th>
+              <th className="px-3 py-2 text-right font-label text-[0.625rem] uppercase tracking-[0.1em] text-muted-foreground"
+                title="Average time to resolve sessions in this domain. Green: &lt;10 min, Amber: 10–20 min, Red: &gt;20 min. Lower is better.">
+                Avg Resolution
+              </th>
             </tr>
           </thead>
           <tbody>
@@ -138,13 +142,32 @@ export default function CoverageHeatmap({ data }: CoverageHeatmapProps) {
                     {(row.guided_rate * 100).toFixed(1)}%
                   </span>
                 </td>
+                <td className="px-3 py-2 text-sm text-right">
+                  {row.avg_resolution_minutes == null ? (
+                    <span className="text-muted-foreground">—</span>
+                  ) : (
+                    <span
+                      className={cn(
+                        'inline-block rounded px-1.5 py-0.5 text-xs font-medium',
+                        row.avg_resolution_minutes < 10
+                          ? 'bg-emerald-400/10 text-emerald-400'
+                          : row.avg_resolution_minutes <= 20
+                            ? 'bg-amber-400/10 text-amber-400'
+                            : 'bg-rose-500/10 text-rose-500',
+                      )}
+                      title={`Avg resolution: ${row.avg_resolution_minutes.toFixed(1)} min — ${row.avg_resolution_minutes < 10 ? 'Good (<10 min)' : row.avg_resolution_minutes <= 20 ? 'Needs Improvement (10–20 min)' : 'Slow (>20 min)'}`}
+                    >
+                      {row.avg_resolution_minutes.toFixed(1)} min
+                    </span>
+                  )}
+                </td>
               </tr>
             ))}
           </tbody>
           {data.unmapped_session_count > 0 && (
             <tfoot>
               <tr>
-                <td colSpan={6} className="px-3 py-2 text-xs text-muted-foreground">
+                <td colSpan={7} className="px-3 py-2 text-xs text-muted-foreground">
                   {data.unmapped_session_count} sessions had no domain classification
                 </td>
               </tr>

frontend/src/components/analytics/FlowQualityTable.tsx

@@ -12,6 +12,12 @@ interface FlowQualityTableProps {
 type SortColumn = 'name' | 'usage_count' | 'success_rate' | 'last_matched_at' | 'avg_confidence' | 'quality_score'
 type SortDir = 'asc' | 'desc'
 
+const TYPE_LABELS: Record<string, { label: string; color: string }> = {
+  troubleshooting: { label: 'Troubleshooting', color: 'text-primary' },
+  procedural: { label: 'Project', color: 'text-amber-400' },
+  maintenance: { label: 'Maintenance', color: 'text-blue-400' },
+}
+
 function formatRelativeTime(dateStr: string | null): string {
   if (!dateStr) return 'Never'
   const diff = Date.now() - new Date(dateStr).getTime()
@@ -215,6 +221,9 @@ function FlowRow({
           >
             {flow.name}
           </Link>
+          <span className={cn('font-label text-[0.5rem] uppercase tracking-wider ml-2 shrink-0', TYPE_LABELS[flow.tree_type]?.color || 'text-muted-foreground')}>
+            {TYPE_LABELS[flow.tree_type]?.label || flow.tree_type}
+          </span>
           {needsAttention && (
             <span className="shrink-0 bg-amber-400/10 text-amber-400 font-label text-[0.625rem] px-1.5 py-0.5 rounded">
               Needs attention