fix: one password-failure message across every screen (closes #172)

A rejected password was reported three different ways depending on which screen
you were on, including the fragment "Wrong password." which is not a sentence.
All six decryptWithPassword call sites now show the same full sentence.

Strings only -- a wrong password still fails closed on every screen and still
resolves no pending approval.

A test pins the invariant per call site: each decryptWithPassword call is walked
out to its enclosing try and forward to that block's catch, and the prose shown
there must equal the canonical sentence. Per-file matching was not enough, since
a file with two call sites kept passing while one of them diverged.

src/popup/views/deleteWallet.js

@@ -74,7 +74,8 @@ function init(_ctx) {
         try {
             await decryptWithPassword(wallet.encryptedSecret, pw);
         } catch (_e) {
-            $("delete-wallet-flash").textContent = "Wrong password.";
+            $("delete-wallet-flash").textContent =
+                "That password is incorrect. Please try again.";
             $("delete-wallet-flash").style.visibility = "visible";
             btn.disabled = false;
             btn.classList.remove("text-muted");