feat(matching-runs): add per-run aggregate stats and UI display

- Admin list endpoint returns totalSuggestions, assignedCount, aggregatedNotFoundCount per run
- UI: show Total/Matched/Not found columns using fresh aggregates
- Add anchor link Run #ID and wording 'Pairs created in this run'

backend/prisma/migrations/20251130122800_add_origin_run_id_to_suggestions/migration.sql

@@ -0,0 +1,13 @@
+-- Add origin_run_id column to recording_suggestions
+ALTER TABLE "recording_suggestions" ADD COLUMN "origin_run_id" INTEGER;
+
+-- Add foreign key to matching_runs
+ALTER TABLE "recording_suggestions"
+  ADD CONSTRAINT "recording_suggestions_origin_run_id_fkey"
+  FOREIGN KEY ("origin_run_id") REFERENCES "matching_runs"("id")
+  ON DELETE SET NULL ON UPDATE CASCADE;
+
+-- Simple index to support joins by origin_run_id
+CREATE INDEX IF NOT EXISTS "recording_suggestions_origin_run_id_idx"
+  ON "recording_suggestions"("origin_run_id");
+

backend/src/routes/admin.js

@@ -104,6 +104,30 @@ router.get('/events/:slug/matching-runs', authenticate, async (req, res, next) =
       },
     });
 
+    // Aggregate fresh stats per run from recording_suggestions (origin_run_id)
+    // Cheap and valuable: shows actual created pairs in this run.
+    if (runs.length > 0) {
+      const runIds = runs.map(r => r.id);
+      // Single SQL query for all listed runs
+      const placeholders = runIds.join(',');
+      const aggRows = await prisma.$queryRawUnsafe(
+        `SELECT origin_run_id AS "originRunId",
+                COUNT(*)::int AS "totalSuggestions",
+                COUNT(*) FILTER (WHERE recorder_id IS NOT NULL)::int AS "assignedCount",
+                COUNT(*) FILTER (WHERE status = 'not_found')::int AS "notFoundCount"
+         FROM recording_suggestions
+         WHERE event_id = ${event.id} AND origin_run_id IN (${placeholders})
+         GROUP BY origin_run_id`
+      );
+      const aggByRun = new Map(aggRows.map(r => [r.originRunId, r]));
+      for (const r of runs) {
+        const agg = aggByRun.get(r.id) || { totalSuggestions: 0, assignedCount: 0, notFoundCount: 0 };
+        r.totalSuggestions = agg.totalSuggestions;
+        r.assignedCount = agg.assignedCount;
+        r.aggregatedNotFoundCount = agg.notFoundCount; // keep original notFoundCount for backward compat
+      }
+    }
+
     res.json({ success: true, count: runs.length, data: runs });
   } catch (error) {
     next(error);

frontend/src/components/events/MatchingRunsSection.jsx

@@ -101,6 +101,7 @@ export default function MatchingRunsSection({ slug }) {
               <th className="px-3 py-2 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Ended</th>
               <th className="px-3 py-2 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Trigger</th>
               <th className="px-3 py-2 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Status</th>
+              <th className="px-3 py-2 text-right text-xs font-medium text-gray-500 uppercase tracking-wider">Total</th>
               <th className="px-3 py-2 text-right text-xs font-medium text-gray-500 uppercase tracking-wider">Matched</th>
               <th className="px-3 py-2 text-right text-xs font-medium text-gray-500 uppercase tracking-wider">Not found</th>
             </tr>
@@ -117,7 +118,7 @@ export default function MatchingRunsSection({ slug }) {
             ) : (
               runs.map((run) => (
                 <>
-                  <tr key={run.id}>
+                  <tr key={run.id} id={`run-${run.id}`}>
                     <td className="px-3 py-2 text-sm text-gray-700">
                       <button
                         onClick={() => toggleViewPairs(run.id)}
@@ -139,13 +140,17 @@ export default function MatchingRunsSection({ slug }) {
                         {run.status}
                       </span>
                     </td>
-                    <td className="px-3 py-2 text-sm text-right text-gray-700">{run.matchedCount}</td>
+                    <td className="px-3 py-2 text-sm text-right text-gray-700">{run.totalSuggestions ?? '-'}</td>
-                    <td className="px-3 py-2 text-sm text-right text-gray-700">{run.notFoundCount}</td>
+                    <td className="px-3 py-2 text-sm text-right text-gray-700">{run.assignedCount ?? run.matchedCount}</td>
+                    <td className="px-3 py-2 text-sm text-right text-gray-700">{run.aggregatedNotFoundCount ?? run.notFoundCount}</td>
                   </tr>
                   {expandedRunId === run.id && (
                     <tr>
                       <td colSpan="7" className="px-3 py-2 bg-gray-50">
-                        <div className="text-sm text-gray-800 font-medium mb-2">Pairs created in this run</div>
+                        <div className="flex items-center justify-between mb-2">
+                          <div className="text-sm text-gray-800 font-medium">Pairs created in this run</div>
+                          <a href={`#run-${run.id}`} className="text-xs text-primary-600 hover:underline">Run #{run.id}</a>
+                        </div>
                         {pairsLoading && (!pairsByRun[run.id] || pairsByRun[run.id].length === 0) ? (
                           <div className="text-gray-500">Loading pairs...</div>
                         ) : (pairsByRun[run.id] && pairsByRun[run.id].length > 0 ? (