fix: drop the per-column filters from the recent-QSO grid

They searched only the rows on screen. With the grid holding the most recent
page, filtering a column for RSGB-IOTA across a 28 000-QSO log returned nothing
— which reads as "the log does not contain it", not "it is not on this page".
That is how an import that had worked perfectly came to be reported as broken:
the tool answered a narrower question than the one being asked, and said so
only by being empty.

The advanced filter queries the whole logbook and is the honest instrument. The
headers also get back the width the filter menu icon was taking, which is the
smaller reason but a welcome one on a grid this dense.

No saved filter can be stranded by this: the grid persists widths, sort and
visibility, never a filter model.

frontend/src/components/RecentQSOsGrid.tsx

@@ -444,10 +444,18 @@ export function RecentQSOsGrid({ rows, myGrid, selectAllSignal, selectRowSignal,
     if (widthUps.length) api.setColumnWidths(widthUps);
   }, [awardCols, awardShown]);
 
+  // No column filters here, deliberately. This grid holds only the most recent
+  // page of QSOs, so a column filter searches THOSE rows and nothing else — and
+  // an empty result then reads as "the log does not contain it" rather than "it
+  // is not on this page". An operator hunting an imported CONTEST_ID across
+  // 28 000 QSOs found nothing and reasonably concluded the import had dropped it.
+  //
+  // The advanced filter queries the whole logbook and is the honest tool for it.
+  // Removing the filter also gives each header back the width of its menu icon.
   const defaultColDef = useMemo<ColDef>(() => ({
     sortable: !passOrder,
     resizable: true,
-    filter: true,
+    filter: false,
     suppressMovable: false,
   }), [passOrder]);