fix: the address screen shows a token just added at its fetched balance, not 0.0000 (closes #516)

A balance refresh that returns now draws the balances on AddressDetail or
AddressToken again when that screen is up, not only the wallet list. Their
transaction lists are left alone.

Every add path on AddToken and SettingsAddToken tracks a token through
trackToken(), which gives the tracked record `balanceNotFetched: true`. While
the field is set, the token's line reads `quantity unknown` instead of 0.0000,
and Send reads its balance as unknown. refreshBalances() now resolves with the
tracked tokens whose balance it read at every address. The popup's refresh
deletes the field from those tokens in the stored record and leaves the rest of
the stored list as it is. Removing the token removes the field, and each network
keeps its own records.

Model: opus-5-5

src/popup/views/addressToken.js

@@ -50,37 +50,18 @@ function show() {
     const addr = wallet.addresses[state.selectedAddress];
     const ai = state.selectedAddress;
     const tokenId = state.selectedToken;
-
-    // Determine token symbol and balance
-    let symbol, amount, price;
     const knownToken = TOKEN_BY_ADDRESS.get(tokenId.toLowerCase());
-    if (tokenId === "ETH") {
-        symbol = nativeCurrency();
-        amount = parseFloat(addr.balance || "0");
-        price = getPrice("ETH");
-    } else {
-        const tb = (addr.tokenBalances || []).find(
-            (t) => t.address.toLowerCase() === tokenId.toLowerCase(),
-        );
-        symbol = resolveSymbol(
-            tokenId,
-            addr.tokenBalances,
-            state.trackedTokens,
-        );
-        // null when the scale is unknown: no quantity to show, and none to
-        // price. balanceLine() states that rather than printing 0.0000.
-        amount = tb ? unknownableAmount(tb.balance) : 0;
-        price = getPrice(tokenId);
-    }
-
-    currentSymbol = symbol;
+    currentSymbol =
+        tokenId === "ETH"
+            ? nativeCurrency()
+            : resolveSymbol(tokenId, addr.tokenBalances, state.trackedTokens);
 
     $("address-token-title").textContent =
         wallet.name +
         " \u2014 Address " +
         (ai + 1) +
         " \u2014 " +
-        displaySymbol(symbol);
+        displaySymbol(currentSymbol);
 
     // Blockie
     const blockieEl = $("address-token-jazzicon");
@@ -102,13 +83,7 @@ function show() {
     $("address-token-line").dataset.full = addr.address;
     attachCopyHandlers($("address-token-line"));
 
-    // USD total for this token only
-    const usdVal = price && amount !== null ? amount * price : null;
-    const usdStr = formatUsd(usdVal);
-    $("address-token-usd-total").innerHTML = escapeHtml(usdStr) || " ";
-
-    // Single token balance line (no tokenId — not clickable here)
-    $("address-token-balance").innerHTML = balanceLine(symbol, amount, price);
+    renderBalance();
 
     // Token contract details (ERC-20 only)
     const contractInfo = $("address-token-contract-info");
@@ -170,6 +145,47 @@ function show() {
     loadTransactions(addr.address, tokenId);
 }
 
+// The USD total and the balance line of the selected token. Drawn again by
+// each balance refresh that returns while this screen is up
+// (doRefreshAndRender() in src/popup/index.js), which leaves the rest of the
+// screen as it is.
+function renderBalance() {
+    const addr =
+        state.wallets[state.selectedWallet].addresses[state.selectedAddress];
+    const tokenId = state.selectedToken;
+    let amount, price;
+    if (tokenId === "ETH") {
+        amount = parseFloat(addr.balance || "0");
+        price = getPrice("ETH");
+    } else {
+        const id = tokenId.toLowerCase();
+        const tb = (addr.tokenBalances || []).find(
+            (t) => t.address.toLowerCase() === id,
+        );
+        const tracked = state.trackedTokens.find(
+            (t) => t.address.toLowerCase() === id,
+        );
+        // null when the scale is unknown, or when no refresh has read the
+        // balance of a token just added: no quantity to show, and none to
+        // price. balanceLine() states that rather than printing 0.0000.
+        if (tb) amount = unknownableAmount(tb.balance);
+        else amount = tracked && tracked.balanceNotFetched ? null : 0;
+        price = getPrice(tokenId);
+    }
+
+    // USD total for this token only
+    const usdVal = price && amount !== null ? amount * price : null;
+    const usdStr = formatUsd(usdVal);
+    $("address-token-usd-total").innerHTML = escapeHtml(usdStr) || " ";
+
+    // Single token balance line (no tokenId — not clickable here)
+    $("address-token-balance").innerHTML = balanceLine(
+        currentSymbol,
+        amount,
+        price,
+    );
+}
+
 async function loadTransactions(address, tokenId) {
     const networkId = state.networkId;
     try {
@@ -383,4 +399,4 @@ function init(_ctx) {
     });
 }
 
-module.exports = { init, show };
+module.exports = { init, show, renderBalance };