fix(channels): drop a stale column filter when sent to "without full history"

A focus-channel deep-link sets (and persists) the channel-name column filter
via the DataTable's externalFilter. That persisted value then survived into
unrelated visits: clicking the header's "N without full history" link landed
on the right tab with the right status chip, but a leftover name filter (e.g.
a channel focused in a past session) hid every row — "No channels".

Add a resetFiltersToken to DataTable that clears its column filters when it
advances, and bump it from the header intent. The token's ref starts at 0 so
the clear fires even when the table remounts on navigation, while a plain
reload (token still 0) keeps the user's persisted filters.

frontend/src/App.tsx

@@ -148,6 +148,9 @@ export default function App() {
     setChannelsViewState(v);
     localStorage.setItem(CHANNELS_VIEW_KEY, v);
   };
+  // Bumped to tell the channel manager to drop a stale column filter when we send the user
+  // there to see a specific set (the header's "without full history" link).
+  const [channelsFilterReset, setChannelsFilterReset] = useState(0);
   // "Focus this channel in the manager": jump to the Channels page and seed its name filter
   // so the channel is isolated. Cleared when leaving the page so it doesn't re-apply later.
   const [focusChannelName, setFocusChannelName] = useState<string | null>(null);
@@ -423,6 +426,7 @@ export default function App() {
           onGoToFullHistory={() => {
             setChannelFilter("needs_full");
             setChannelsView("subscribed"); // the status filter applies to the subscriptions tab
+            setChannelsFilterReset((n) => n + 1); // drop any stale column filter hiding the rows
             setPage("channels");
           }}
         />
@@ -449,6 +453,7 @@ export default function App() {
               setStatusFilter={setChannelFilter}
               view={channelsView}
               setView={setChannelsView}
+              filtersResetToken={channelsFilterReset}
               onOpenWizard={() => setWizardOpen(true)}
               onViewChannel={(id, name) => {
                 setFilters({ ...filters, channelId: id, channelName: name, show: "all" });