Fix Hot Run tab crash when a result has fewer queries

The `pandas` result file has only 42 query entries (missing one), and
the `hot` metric is the only one that does not filter out in-memory
systems. Switching to Hot Run accessed `elem.result[42][run_num]` and
crashed with `Cannot read properties of undefined (reading '0')`.

Make the JS robust to short result arrays:
- `selectRun` returns null when given null/undefined timings
- baseline computation uses optional chaining

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: alexey-milovidov

index.html

@@ -710,6 +710,7 @@ <h2>Detailed Comparison</h2>
 const combined_hot_share = 0.6;
 
 function selectRun(timings, metric) {
+    if (timings == null) return null;
     const cold_timing = timings[0];
     const hot_timing = (timings[1] !== null && timings[2] !== null ? Math.min(timings[1], timings[2]) : null);
 
@@ -777,7 +778,7 @@ <h2>Detailed Comparison</h2>
 
     const baseline_data = [...filtered_data[0].result.keys()].map(query_num =>
         [...Array(3).keys()].map(run_num =>
-            Math.min(...filtered_data.filter(elem => !elem.fake).map(elem => elem.result[query_num][run_num]).filter(x => x != null))));
+            Math.min(...filtered_data.filter(elem => !elem.fake).map(elem => elem.result[query_num]?.[run_num]).filter(x => x != null))));
 
     const min_load_time = Math.min(...filtered_data.map(elem => elem.load_time).filter(x => x && x > 5));
     const min_data_size = Math.min(...filtered_data.map(elem => elem.data_size).filter(x => x && x > 1e9));