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.
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

tests/support/popupBoot.js

@@ -279,10 +279,11 @@ async function bootPopup(stored, options) {
         getAddressValue: () => ({ usd: null, partial: false }),
     }));
     // scanForAddresses() answers in the real one's shape, a scan that found
-    // no used address: AddWallet reads `addresses` from it.
+    // no used address: AddWallet reads `addresses` from it. refreshBalances()
+    // answers as a refresh that read no tracked token's balance.
     jest.doMock("../../src/shared/balances", () => ({
         fetchTokenBalances: jest.fn(async () => []),
-        refreshBalances: jest.fn(async () => {}),
+        refreshBalances: jest.fn(async () => []),
         dropUntrackedTokens: jest.requireActual("../../src/shared/balances")
             .dropUntrackedTokens,
         lookupTokenInfo: jest.fn(async () => null),