feat(telemetry): matchup and direction context in timelines; live error groups

- h2h_viewed carries who-v-who, stats_sorted carries asc/desc via a
  timeline-only context prop
- error browser aggregates raw rows so new groups appear immediately
- catalogs re-extracted for shifted line references

src/features/bracket/components/match-dock.tsx

@@ -176,7 +176,12 @@ const MatchDock = ({ match, onClose }: MatchDockProps) => {
                         variant="subtle"
                         size="sm"
                         onClick={() => {
-                          track("h2h_viewed", { source: "match_dock" });
+                          track("h2h_viewed", {
+                            source: "match_dock",
+                            context: [match?.home?.name, match?.away?.name]
+                              .filter(Boolean)
+                              .join(" v "),
+                          });
                           h2hSheet.open();
                         }}
                         aria-label={t`View head-to-head`}