✨ fix: ensure table shows correct loading state on first render & during search

Frontend (`ChannelsTable.js`)
1. Initialize `loading` state to `true` so the spinner is visible while the first data request is in-flight.
2. Set `<Table>` prop `loading={loading || searching}` — the spinner now appears for both the initial load and any subsequent search requests.

Result
Users immediately see a loading indicator on page entry and whenever a search is running, improving perceived responsiveness.

web/src/components/table/ChannelsTable.js

@@ -1876,7 +1876,7 @@ const ChannelsTable = () => {
           }
           className="rounded-xl overflow-hidden"
           size="middle"
-          loading={loading}
+          loading={loading || searching}
         />
       </Card>