fix: a popup reload no longer logs the requests it cancels on most screens (closes #475)

The transaction lists and ENS name lookups on the address and token
screens, the address scan after a wallet is created, the endpoint checks
in Settings, the wait screen's receipt check, the Send screen's Max fee
estimate and the token lookup on both add-token screens now check the
signal the popup aborts on pagehide before reporting a failed request.
scanForAddresses(), resolveEnsNames() and lookupTokenInfo() take the
signal.

End-to-end tests reload the popup on the address screen and during the
address scan with their requests held. Jest tests show each of these
reports a real failure and stays silent once the popup has closed. The
transaction detail and confirmation screens are left out: they discard
the popup context that carries the signal.

Model: opus-5-5

src/popup/views/addressToken.js

@@ -219,6 +219,7 @@ async function loadTransactions(address, tokenId) {
                     counterparties,
                     state.rpcUrl,
                     state.networkId,
+                    ctx.pageClosed,
                 );
             } catch {
                 ensNameMap = new Map();
@@ -227,6 +228,9 @@ async function loadTransactions(address, tokenId) {
 
         renderTransactions(txs);
     } catch (e) {
+        // Cancelled by the popup closing, not failed: see pageClosed in
+        // src/popup/index.js.
+        if (ctx.pageClosed.aborted) return;
         log.errorf("loadTransactions failed:", e.message);
         $("address-token-tx-list").innerHTML =
             '<div class="text-muted text-xs py-1">Failed to load transactions.</div>';