feat: add miner detail view

backend/app/repairs/center_repository.py

@@ -315,6 +315,28 @@ class RepairCenterRepository:
             connection.close()
         return {"items": items, "summary": summary, "location_options": options}
 
+    def list_miner_repairs(self, miner_id) -> list[dict[str, Any]]:
+        """Return a bounded, exact repair history for one durable miner."""
+        ctes = self._ctes(show_miners=False, show_locations=False)
+        connection = self._connection_factory()
+        try:
+            with connection.cursor(row_factory=dict_row) as cur:
+                cur.execute(
+                    f"""
+                    {ctes}
+                    SELECT candidate.* FROM candidates AS candidate
+                    WHERE candidate.miner_id = %s
+                    ORDER BY candidate.active DESC,
+                        candidate.opened_at DESC NULLS LAST,
+                        candidate.repair_id NULLS LAST
+                    LIMIT 50
+                    """,
+                    (miner_id,),
+                )
+                return [dict(row) for row in cur.fetchall()]
+        finally:
+            connection.close()
+
     def summarize_active_repairs(self) -> dict[str, Any]:
         """Return exact active counts without loading Repair Center rows."""
         ctes = self._ctes(show_miners=False, show_locations=False)