Show active address ETH balance and USD value in headline

The headline now shows the active address's balance as
"x.yyyy ETH ($z.aa USD)" instead of the sum across all wallets.

src/popup/views/home.js

@@ -12,14 +12,32 @@ const QRCode = require("qrcode");
 const { deriveAddressFromXpub } = require("../../shared/wallet");
 const {
     formatUsd,
+    getPrice,
     getAddressValueUsd,
-    getTotalValueUsd,
 } = require("../../shared/prices");
 
+function findActiveAddr() {
+    for (const w of state.wallets) {
+        for (const a of w.addresses) {
+            if (a.address === state.activeAddress) return a;
+        }
+    }
+    return null;
+}
+
 function renderTotalValue() {
     const el = $("total-value");
     if (!el) return;
-    el.textContent = formatUsd(getTotalValueUsd(state.wallets));
+    const addr = findActiveAddr();
+    if (!addr) {
+        el.textContent = "";
+        return;
+    }
+    const ethBal = parseFloat(addr.balance || "0");
+    const ethStr = ethBal.toFixed(4) + " ETH";
+    const usd = getAddressValueUsd(addr);
+    const usdStr = usd !== null ? " (" + formatUsd(usd) + " USD)" : "";
+    el.textContent = ethStr + usdStr;
 }
 
 const EXT_ICON =